Dear applicant the fact is every year number of BSNL Junior Telecom Officers are recruited based on the GATE score, so there is nothing to panick as your hard work and dedication will guide you to your path of success, apply through the official online website and register accordingly to avoid the possibility of fraud or harassment. You can also refer the following books available online

BSNL Junior Engineer (JE) Examination Important Study Materials & Objective Type Q & A "? K.R. GOVINDAN

Guide to BSNL Telecom Technical Assistant(TTA) Junior Engineer (Erstwhile TTA) "? GKP

BSNL "? TTA (Telecom Technical Asst. Exam) "? Chandresh Agrawal & Team

Good luck!!!