In this page, you will find links to various articles which I have used for identification of coins and understanding of the history behind.
Anantasayanam and Thirai Cash of Venad and Travancore - Catalogue
Catalogue of Thirai Cash of Venad and Travancore by Barbara Mears.
Very useful to understand the symbols in verify the Cash coins.
Anantasayanam and Thirai Cash of Venad and Travancore
An excellent article by Barbara Mears.
Some information about Travancore and Thirai Cash can be found in this article.
A History of Travancore from the Earliest Times, Volume 1
A book by P. Shungoonny Menon about history of Travancore written in 1984.
Traversing Travancore Through the Ages on Coins
A book by Beena Sarasan.