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1 _ Series/1 GC PROGRAM PRODUCT 1 IBM Series/1 FORTRAN IV I ntrod ution Program Numbers 5719-F F03 0 lee : eel II [] 10...,!...---' '* rr' 0 ;p : f'...) m 0!l]J1 []J 0 [[] (( b "'l V

2 _.- Series/l GC PROGRAM PRODUCT IBM Series/1 FORTRAN IV Introdution Program Numbers 5719-F F03 o

3 This publiation is for planning purposes only. The information herein is subjet to hange before the produts desribed beome available. o First Edition (February 1977) This edition applies to IBM Series/1 FORTRAN IV (ompiler and objet support library), Program Number 5719-F01, and IBM Series/1 Realtime Subroutine Library, Program Number 5719-F03. Signifiant hanges or additions to the ontents of this publiation will be reported in subsequent revisions or Tehnial Newsletters. Requests for opies of IBM publiations should be made to your IBM representative or the IBM branh offie serving your loality. A form for readers' omments is provided at the bak of this publiation. If the form has been removed, send your omments to IBM Corporation, Systems Publiations, Department 27T, P. O. Box 1328, Boa Raton, Florida Comments beome the property of IBM. Copyright International Business Mahines Corporation 1977 ii GC

4 Contents C - Prefae v Series/1 FORTRAN IV Program Produt Resoures for Series/1 FORTRAN IV 3 Minimum System Configuration 3 Seondary Storage Estimates 3 Libraries 3 FORTRAN IV Objet Support Library 3 FOR TRAN IV Realtime Subroutine Library 4 Mathematial and Funtional Subroutine Library 5 FORTRAN IV Diagnostis 5 FORTRAN IV Error Handling 5 FORTRAN IV Language Elements 6 Multiple Program Support 6 Logial and Relational Operations 6 Bit-Level Operations 6 Diret-Aess Input/Output 7 Additional READ and WRITE Parameters 7 Devie-Independent Input/Output 7 List-Direted Input/Output 7 Double-Preision 7 Carriage Control for Reports 7 Six-Charater Names 7 Expanded Charater Set 7 A Comparison of FOR TRAN IV Features 8 FORTRAN IV Language Statements 10 Index 13 - C '" Contents iii

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6 Prefae This manual introdues the Series/l FORTRAN IV program produt (ompiler and objet support library) by providing an overview of the Series/! FORTRAN IV language elements, the FORTRAN IV-supplied objet support library, and the FORTRAN IV Realtime Subroutine Library and the Mathematial and Funtional Subroutine Library program produts. The resoures required for the preparation and exeution of your FORTRAN IV appliation programs are summarized and a list of the minimum system onfiguration is provided. The language is a subset of Amerian National Standard FORTRAN, , and inludes the Amerian National Standard (ANS) Basi FORTRAN, , with the exeption of objet time formats, adjustable dimensions, COMPLE data type, G-format speifiations, and two-level FORMAT parenthesis. Also inluded are IBM extensions to the language. This publiation is intended to be used by management personnel as a planning and evaluation aid and by programmers as an overview of the features and harateristis of Series/l FORTRAN IV. Assoiated Publiations IBM Series/l FORTRAN IV: Language Referene, GC IBM Series/l System Summary, GA IBM Series/l Realtime Programming System: Introdution and Planning Guide, GC IBM Series/l Program Preparation Subsystem: Introdution, GC IBM Series/l Mathematial and Funtional Subroutine Library: Introdution, GC o Prefae v

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8 Series/1 FORTRAN IV Program Produt CI The Series/1 FORTRAN IV program produt is designed for programming appliations on the IBM Series/1 omputer and onsists of a ompiler and objet support library. The FORTRAN IV ompiler produes ode with emphasis on ompat storage and exeution speed. FORTRAN IV and your Series/1 omputer together allow you to: Perform alulations and make deisions Read information from sensor devies and send ommands bak to ontrolling devies Shedule programs and input/output operations Create reports and disk data sets FORTRAN IV is a high-level, mathematially-oriented language designed to manipulate numerial data and format input/output operations. In addition to being easily learned and understood, appliations an be programmed without knowledge of the Series/1 assembler language. Programming produtivity is inreased sine high-level languages require less oding than assembler languages. An example of the differene in these two languages is: Mathematial formula: I = J + K - L FORTRAN IV solution Series/1 assembler solution J 3 MVW J,R7 K 2 AW K,R7 L 3 SW L,R7 MVW R7,I I J + K - L I DS F J DS F K DS F L DS F The FORTRAN IV ompiler is a serially reusable, single task set whih exeutes in a bath environment under the IBM Series/1 Program Preparation Subsystem (hereafter referred to as Program Preparation Subsystem) job stream proessor. During exeution, the ompiler operates under the ontrol of the IBM Series/1 Realtime Programming System (hereafter referred to as Realtime Programming System) failities required for your appliation programs. FORTRAN IV objet modules are ombined with library routines by the Program Preparation Subsystem appliation builder to form load modules whih exeute under the ontrol of the Realtime Programming System. Figure 1 desribes the preparation of Series/1 FORTRAN IV programs. Series/1 FORTRAN IV Program Produt

9 Compiling - translating FORTRAN IV soure statements into an objet module. ( " J FORTRAN IV ompiler Appliation building - ombining FORTRAN IV objet modules with library modules to form an exeutable task set or a reproessable load module (suitable as input to the appliation builder for subsequent proessing with other load modules to form a task set). Appliation builder or Figure 1. Preparation of Series/l FORTRAN IV programs (' 2 GC

10 Resoures for Series/1 FORTRAN IV IBM Series/1 FORTRAN IV ompiles under the ontrol of the Program Preparation Subsystem (Program Produt 5719-AS1). Objet ode exeutes either in the Program Preparation Subsystem environment or under ontrol of the Realtime Programming System (Program Produt 5719-PCl). Floating-point support, either hardware or emulation pakage, is required for objet exeution if the user performs floating-point (REAL) operations. Minimllm System Configuration The minimum Series/1 system onfiguration for preparation and exeution of your FORTRAN IV program is as follows: Operator Station 4953 or 4955 Proessor with storage for the Realtime Programming System and 16KB user partition for the ompiler Disk Storage Unit 4964 Diskette Unit Devie for output, for example: 4962 Disk Storage Unit, 4964 Diskette Unit, 4974 Printer Seondary Storage Estimates Compiler: 450 setors (see Note) JSP environment lists: 45 setors Intermediate file: 400 setors (see Note) Objet support library: 360 setors FORTRAN IV Realtime Subroutine Library: 200 setors MFSL requirements: See Mathematial and Funtional Subroutine Library: Introdution Soure input file: Depends on program to be ompiled Objet output file: Depends on program ompiled Note. Blok size of 256 bytes is required. For optimum performane, setor size should be 256 bytes. Libraries Series/1 FORTRAN IV provides you with modular implementation of all library routines, thereby reduing program size. Library routines are re-entrant and an be used by multiple appliation programs. FORTRAN IV Objet SlIpport Library The FORTRAN IV objet support library ontains subroutines whih are ombined, as neessary, with the objet modules produed by the FORTRAN IV ompiler. The objet support library routines perform: Input/output proessing Error handling Expliit and impliit servie operations When you need a library routine, the ompiler generates a all to it. During proessing by the Program Preparation Subsystem appliation builder, a opy of the library routine is made part of the storage load. The storage load module is then ready to exeute on your Series/1 omputer. Series/1 FORTRAN IV Program Produt 3

11 FORTRAN IV Realtime SIIbrollti"e Library The FORTRAN IV Realtime Subroutine Library: Program Produt S719-F03, provides realtime system support. The subroutines ontained in this library onform to the Instrument Soiety of Ameria (ISA) Standard, S , and are available to your programs via the CALL statement. The proedures inlude: Exeutive funtion subroutines, whih provide the ability to start, stop, or delay the exeution of programs. These subroutines are: START exeute TRNON exeute at a speified time WAIT suspend exeution Proess I/O subroutines, whih aess analog and digital points for both input and output. These subroutines are: Analog AISQW AIRDW AOW Digital reads input points in sequene reads input points in user-speified sequene writes output registers in user-speified sequene DIW reads input registers DOMW sets and resets user-seleted DO points DOL W sets or resets user-seleted DO groups System servie interfae subroutines, whih aess system servies. These subroutines are: $ATACH attah task $A WAIT wait on ompletion of event $CON onnet task to PI interrupt $DEQUE remove element from queue $DFNEV define event $DFNQU define storage queue $DFNRS define resoure $DISCN disonnet from PI interrupt $DL TEV delete event $DL TQU delete queue $DL TRS delete resoure $DTACH detah (terminate) task $ENQUE add element to queue $MDSST modify system sheduler table $MDSTT modify system task set table $POST post ompletion of event $RDTOD read time-of-day $RELRS release resoure $REQRS request resoure $SERT set task error exit routine $SETRL set ROLLIN/ROLLOUT status $TSQUE queue task set for exeution $TSSTP terminate task set exeution $WRTOD write time-of-day Time subroutine, whih determines the urrent time of day. This subroutine is: TIME Date subroutine, whih determines the urrent alendar date. This subroutine is: DATE (; I 4 GC

12 o o Matllematial and Fllntional SIIbrolltine Library The Mathematial and Funtional Subroutine Library: Program Produt S719-LMI is a prerequisite and provides the following subroutines: Mathematial: ar tangent, one or two arguments; osine; exponential funtion; exponentiation; hyperboli tangent; logarithms, ommon and natural; maximum value; minimum value; modular arithmeti; positive differene; sine; square root; transfer of sign. Conversion: EBCDIC to floating point; EBCDIC to integer; floating point to EBCDIC; integer to EBCDIC Error-heking: funtion test; floating-point divide exeption; floating-point overflow / underflow. FORTRAN IV Diagnostis FORTRAN IV -provided diagnosti aids or servies assist in program reation and debugging. Soure statements are verified for proper syntax during ompilation. For faster analysis, statement syntax an be heked without produing objet ode. These statements produe a log of program ativity (suh as a trae of routine labels) while your program is exeuting. You may request a variety of maps and listings from the FORTRAN IV ompiler: Listing of soure statements Statement label map with relative addresses Map of storage loations for variables and arrays Hexadeimal listing of the objet dek Cross-referene index for symbols and labels The FORTRAN IV library ontains routines whih provide diagnosti information in ase error onditions our during program exeution. You may use these routines or supply your own. The debug faility onsists of a DEBUG speifiation statement, an AT debug paket identifiation statement, and the TRACE statement. These statements are used to speify the desired debugging operations for a program. FORTRAN IV Error Handling While your FORTRAN IV program is exeuting, errors may result from invalid data usage or hardware failures. FORTRAN IV assists in deteting these errors and taking appropriate ation. The mathematial routines hek the arguments passed to them for validity. If an argument is invalid, orretive ation is taken and proessing ontinues uninterrupted. For example, if you pass a negative argument to the ALOG (natural algorithm) funtion, the absolute value of the argument is used. You an hek within your FORTRAN IV program to determine whether orretive ation has been taken. Other errors an be heked within your FORTRAN IV program. These inlude: Overflow Underflow Divide hek Funtion ode Arithmeti result greater than the maximum valid real number Arithmeti result less than the smallest valid nonzero real number Attempt to divide a real number by zero Illegal argument/invalid data For I/O devie errors, FORTRAN IV offers several levels of error handling. The lowest level of support is the printing of an informative message prior to program termination. If you want your program to take some partiular ation Series/l FORTRAN IV Program Produt 5

13 prior to termination, you an speify an error handling routine (using the ERRIT subroutine) to reeive ontrol when I/O errors our. An additional level of error handling is provided by the ERR= and END= parameters on I/O statements to speify different error-handling routines for different devies and f ' situations. \. ; FORTRAN IV Language Elements Series/1 FORTRAN IV is a subset of Amerian National Standard (ANS) FORTRAN, , and inludes Amerian National Standard Basi FORTRAN, , with the exeption of objet time formats, adjustable dimensions, COMPLE data type, G-format speifiations, and two-level FORMAT parenthesis. Series/1 FORTRAN IV also has many language elements not provided by ANS Basi FORTRAN; these are referred to olletively as the Series/1 FORTRAN IV extensions. The Series/1 FORTRAN IV extensions adapt FORTRAN to the Series/1 environment and provide greater programming flexibility. The signifiane of several extensions follows. Multiple Program Support Three FORTRAN IV statements (PROGRAM, INVOKE, and GLOBAL) permit optimal use of the interrupt sheme. The PROGRAM statement assigns a unique name to eah of several main programs thereby establishing multiple entry points for exeution in response to interrupts. The INVOKE statement permits you to selet the ombination and sequene of programs to be loaded into main storage. The GLOBAL statement establishes a data area ommon to two or more main programs. These three statements help you model your programming support aording to your interrupt onfiguration and allow you to pass information and ontrol between various program elements as onditions warrant. Logial and Relational Operations To aid in making deisions, you an define logial variables and assign them the values true or false. Furthermore, you an evaluate a logial or relational expression with the logial IF statement and take appropriate ation aording to the logial value of the expression. For example, the expression A.GT.B (A greater than B) an be evaluated to be either true or false. In this example,.gt. is a relational operator. The valid logial and relational operators are listed under the setion "FORTRAN IV Language Statements". " p Bit-Level Operations With most FORTRAN languages you work at the word or harater level. To work with sensor-based ativities you need to interrogate and manipulate the bits that orrespond to sensor-based input/output points. Series/1 FORTRAN IV inludes these funtions for bit-level operations: ICOMP or NOT land lor IEOR ISHFT BTEST IBSET IBCLR Logial omplement of an argument Logial and of 2 arguments Logial or of 2 arguments Logial exlusive or of 2 arguments Logial shift of an argument Logial test of a speified bit Set a speified bit Clear a speified bit 6 GC

14 G Diret-Aess IIIPllt / OIItpllt Series/1 FORTRAN IV supports both formatted and unformatted diret-aess data sets on the 4962 Disk Storage Unit. The diret-aess support is implemented through the DEFINE FILE, READ, WRITE, and FIND statements. Additional READ alld WRITE Parameters The ERR= and END= parameters on the READ statement and the ERR= parameter on the WRITE statement give you added flexibility and ontrol. ERR= speifies the label of a routine to handle errors during either a sequential or diret-aess READ or WRITE. END= speifies the label of a routine to handle end-of-file during a sequential READ. Devie-Independellt IIIPllt / OIItpllt Your Series/1 FORTRAN IV programs may be written so that assignment of physial devies to many data sets an be deferred until you are ready to exeute the program. These assignments an then be hanged as required for subsequent use without reording and reompiling the program. List-Direted Inpllt /OIItpllt List-direted I/O simplifies data entry by freeing you from FORMAT statement restritions. Data may be entered (or is written) without regard for olumn or line boundaries. Dollble-Preision Statistial appliations often require greater auray than single-preision (6+ plaes deimal) an offer. The Series/1 FORTRAN IV ompiler, therefore, inludes a double-preision apability. C Carriage Control for Reports You may speify arriage ontrol haraters in report data sets reated by your FORTRAN IV program; these haraters ause the printer arriage to skip lines or start new pages while the data set is being printed. Six-Charater Names Expanded Charater Set Names of up to 6 alphameri haraters may be used for variables, arrays, funtions, and subroutines within Series/1 FORTRAN IV programs. This tehnique, whih allows you to use more meaningful names, improves program doumentation and simplifies maintenane efforts. The Series/1 FORTRAN IV harater set inludes the dollar sign ($) as an alphabeti harater and the ampersand (&) and apostrophe (') as speial haraters in addition to the basi FORTRAN harater set, whih inludes the letters A,B... Z, the numbers 0,1... 9, and the haraters plus (+), minus (-), slash (/), equal (=), asterisk (*), the left and right parentheses, and the blank. Series/l FORTRAN IV Program Produt 7

15 A Comparison of FORTRAN IV Features Series/ ] FORTRAN IV Series/ ] Series/ ] features not FORTRAN IV FORTRAN IV Series/] supported in not available in features not FORTRAN IV IBM System/360 IBM System/360 Series/] FORTRAN IV supported in features not and System/370 and System/370 not available in IBM Basi supported in full FORTRAN full FOR TRAN FORTRAN IV H FORTRAN Features FORTRAN IV ANS FORTRAN IV IV extended features (; Adjustable (objet time) dimensioning ASSIGN ASSIGN GO TO Asynhronous I/O BLOCK DATA COMPLE DATA Debug faility Debug with UNIT, INIT, or SUBCHK Diret-aess I/O statements DISPLAY ENTRY ERR & END parameters in a READ ERR parameter in a WRITE ( " EECUTIVE funtions, Exponentiation or funtion referene in subsripts appearing in I/O lists Extended preision ETERNAL extension FORMAT with G speifiation, or more than 1 level of parenthesis, or adjustable (objet time) format speifiation Funtion names in type statements Generalized subsript form GENERIC GLOBAL Hexadeimal onstant IMPLICIT Initial data values in expliit speifiation statements Integer *2 data type INVOKE L & Z Format Codes ("" '" 8 GC

16 G Series/l FORTRAN IV Series/l Series/l features not FORTRAN IV FORTRAN IV Series/l supported in not available in features not FORTRAN IV IBM System/360 IBM System/360 Series/l FORTRAN IV supported in features not and System /370 and System/370 not available in IBM Basi supported in full FORTRAN full FOR TRAN FORTRAN IV H FORTRAN Features FORTRAN IV ANS FORTRAN IV IV extended features Labeled COMMON Length of variables and arrays as part of type speifiation A subset of FORTRAN IV extended list-direted I/O Literal as atual argument in CALL and funtion referene Literal enlosed in apostrophes LOGICAL*4 LOGICAL*l Logial, literal, and hexadeimal onstants Logial IF Mixed-mode expressions C' Multiple exponentiation w / 0 parentheses to indiate order of omputation NAMELIST PAUSE with literal PRINT Proess I/O subroutines PROGRAM PUNCH RETURN (i) i not a blank READ b list Subprogram dummy arguments enlosed in slashes T and Z format odes Up to 7 dimensions in an array o Series/1 FORTRAN IV Program Produt 9

17 FORTRAN IV Lanpage Statements Speifiation Statements DIMENSION (allowing arrays of up to 7 dimensions) IMPLICIT COMMON, labelled, blank GLOBAL, labelled, blank DATA ETERNAL PROGRAM Type statement, with or without length speifiations, and allowing data initialization and dimension information. EQUIV ALENCE Relational and Logial Operators.EQ. Equal to.ne. Not equal to.lt. Less than.gt. Greater than.le. Less than or equal to.ge. Greater than or equal to.or. Or.AND. And. NOT. Not Control Statements GO TO, unonditional GO TO, omputed GO TO, assigned DO CONTINUE ASSIGN IF, arithmeti IF, logial PAUSE, with optional message or 5-digit identifying number STOP, with optional 5-digit identifying number END Assignment Statements Arithmeti assignment, allowing mixed-mode expression and multiple exponentiation Logi assignment 10 GC

18 Input/ Output Statements READ /WRITE, list-direted READ/WRITE, sequential with optional END= and ERR= parameters on READ; optional ERR= parameter on WRITE READ/WRITE, diret-aess both formatted and unformatted, with optional ERR= parameter on READ and WRITE FIND DEFINE FILE BACKSPACE REWIND END FILE FORMAT, with these odes: A, 0, E, F, I, H, L, P, T,, Z, "literal" Subprograms and Statement Funtions SUBROUTINE FUNCTION, allowing type speifiation of funtion name and redefinition or arguments CALL, allowing subprogram name and literal onstants as arguments RETURN ENTRY, allowing multiple entry points in one subroutine BLOCK DATA, to initialize labelled COMMON Constants INTEGER (INTEGER*4) INTEGER (INTEGER*2) LOGICAL REAL *4 REAL *8 Series/l FORTRAN IV Program Produt 11

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20 Index assignment statements 10 naming tehnique 7 bit-level operations 6 arriage ontrol 7 harater set 7 ompiler 1 onfiguration, minimum system 3 onstants 11 ontrol statements 10 devie-independent I/O 7 diagnostis 5 diret-aess I/O 6 divide-hek 5 double-preision 7 END= parameter 7 ERR= parameter 7 error-handling 5 exeutive funtion subroutines 4 floating-point support 3 FORTRAN IV omparisons 8 FORTRAN IV realtime subroutine library 4 FORTRAN IV objet support library 3 objet support library 3 operator station 3 overflow 5 parameters 7 proess I/O subroutines 4 program preparation 2 READ statement 7 realtime library 4 relational operators 10 resoures 3 single-preision 7 soure statement listing 5 speifiation statements 10 storage estimates 3 storage loation map 5 subprograms and statement funtions 11 symbol and label index 5 system onfiguration, minimum 3 system servie subroutines 4 time and date subroutines 4 hexadeimal listing 5 underflow 5 I/O statements 11 ISA subroutines 4 WRITE statement 7 language statements 10 libraries 3 list-direted I/O 7 listings 5 logial and relational operations logial operators proessor proessor disk storage unit diskette unit printer display station sensor I/O unit 3 mathematial and funtional subroutine library 5 MFSL 5 minimum system onfiguration 3 multiple program support 6 o Index 13

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22 FORTRAN IV: Introdution GC READER'S COMMENT FORM YOUR COMMENTS, PLEASE... Your omments assist us in improving the usefulness of our publiations; they are an important part of the input used in preparing updates to the publiations. All omments and suggestions beome the property of IBM. Please do not use this form for tehnial questions about the system or for requests for additional publiations; this only delays the response. Instead, diret your inquiries or requests to your I BM representative or to the I BM branh offie serving your loality. Co. retions or larifiations needed: Page Comment C (') s 0.., "'T1 0 :» 0" :::J to C :::J CD What is your oupation? Number of latest Tehnial Newsletter (if any) onerning this publiation: Please indiate your name and address in the spae below if you wish a reply. o Thank you for your ooperation. No postage stamp neessary if mailed in the U.S.A. (Elsewhere, an I BM offie or representative will be happy to forward your omments.)

23 GC Your omments, please... This manual is part of a library that serves as a referene soure for IBM systems. Your omments on the other side of this form will be arefully reviewed by the persons responsible for writing and publishing this material. All omments and suggestions beome the property of IBM. Fold Fold First Class Permit 40 Armonk New York Fold = === --_ I nternational Business Mahines Corporation General Systems Division Glenridge Drive N.E. P.O. Box 2150, Atlanta, Georgia (U.S.A. only) Business Reply Mail No postage stamp neessary if mailed in the U.S.A. I BM Corporation Systems Publiations, Dept 27T P.O. Box 1328 Boa Raton, Florida FOld Cl s: f/l \.,J (ii' :;; 'TI 0 :0 -I :0» z a a. :: (').-+ o :::l ::,. (ti a. :i' en?> G) () w r--) 6

24 FORTRAN IV: Introdution GC READER'S COMMENT FORM YOUR COMMENTS, PLEASE... Your omments assist us in improving the usefulness of our publiations; they are an important part of the input used in preparing updates to the publiations. All omments and suggestions beome the property of IBM. Please do not use this form for tehnial questions about the system or for requests for additional publiations; this only delays the response. Instead, diret your inquiries or requests to your I BM representative or to the I BM branh offie serving your loality. Co,"retions or larifiations needed: Page Comment C n S "T1 0 0: 0 ::l to C. ::l ttl What isyouroupation? Number of latest Tehnial Newsletter (if any) onerning this publiation: Please indiate your name and address in the spae below if you wish a reply. o Thank you for your ooperation. No postage stamp neessary if mailed in the U.S.A. (Elsewhere, an IBM offie or representative will be happy to forward your omments.)

25 GC Your omments, please... This manual is part of a library that serves as a referene soure for IBM systems. Your omments on the other side of this form will be arefully reviewed by the persons responsible for writing and publishing this material. All omments and suggestions beome the property of IBM. o S (, \. ; Fold Fold First Class Permit 40 Armonk New York Fold _ International Business Mahines Corporation General Systems Division Glenridge Drive N.E. P.O. Box 2150, Atlanta, Georgia (U.S.A. only) Business Reply Mail No postage stamp neessary if mailed in the U.S.A. I BM Corporation Systems Pu bl iations, Dept 27T P.O. Box 1328 Boa Raton, Florida Fold OJ s:: CJ) 0 ":::D -I :::D» z < (3 a. o ::J. CD a. :i' en?> G') 0 w g w I\) 6, \,

26 _ International Business Mahines Corporation General Systems Division Glenridge Drive N. E. P. O. Box 2150 Atlanta, Georgia (U.S.A. only), If i GC [ij Ul " 0 :D -i :D» z < ;a 0 a. o :::l :;' 5,... (I) a. 5 en Cl (") w w "-l 6 f,..