ISRO conduct written exam for interested candidates. Various books for ISRO preparation are available in market. Candidates can get from their nearest shop dealer.

Exam pattern of ISRO written test was found as follows
Total questions: 80
Time: 90 minutes
Marking: +3 for correct answer -1 for wrong.

Well there are several books available for preparing for ISRO. Any book which is prescribed for the GATE preparation would do sufficiently.

Computer Organization: William Stallings, Morris Mano

Theory of Computation: Aho and Ullman

Compiler Design: Ullman

Operating systems: Galvin

Computer Networks: William Stallings

Book for ISRO exam:

BSNL, DRDO, ISRO: Electronics and Communication Engineering Previous Year - Solved Papers and Practice Papers 2015 Paperback – 2014
by Made Easy (Author)


Apart from these for aptitude and General Knowledge Refer some good magazines like CSR, Manorama Year book for GK sample GK questions and R.S Agarwal