There is not the source of Vallmiki Ramayana, it was all just heared by people and spreaded by mouth thats all. Everyone knows how communications by mouth happens in India, if it is 1 they'll communicate as 100 then 1000, then it'll grow like anything. Thats how Ramayana and Mahabaratha grown, to maintain Hindu idelology few people like Gandhi, Rajaji worte reference books. But that cannot be the reliable proof of existence of Ramayana, Rama, Mahabarataha or Adams bridge.....
