Please see the following RG link and PDF attachment.

Article Conservation of the Southern River Terrapin Batagur affinis ...

There are many actually. Following are some of the ones I found. Hope its helpful.

Good luck.

Article BATAGUR AFFINIS (Southern River Terrapin). DIET IN THE WILD.

Chapter Batagur affinis (Cantor 1847) – Southern River Terrapin, Tuntong.

Conference Paper Tracking the movements of a post-nesting Southern River Terr...

Article Conservation of the Southern River Terrapin Batagur affinis ...

Article Conservation of the southern river terrapin batagur affinis ...

Article DEVELOPMENTAL STAGES OF SOUTHERN RIVER TERRAPIN (Batagur aff...

wah tq so much to both of you Prof/ Dr .

@ Mohd Hairul Mohd Salleh

Please also take a look at the following references.

Article BATAGUR AFFINIS (Southern River Terrapin). DIET IN THE WILD.

Article Tracking the southern river terrapin (Batagur affinis) throu...

Article A new subspecies of Batagur affinis (Cantor, 1847), one of t...

Article Cross-species microsatellite amplification of River Terrapin...

Thanks!

The Ecology, Exploitation and Conservation of River Turtles

By Don Moll, Professor of Biology Don Moll, Edward O. Moll, Professor of Zoology Edward O Moll

Also, this is an older book, but they usually have a gem or two:

Reptilia and Batrachia

📷George Albert 1858-1937 Boulenger WENTWORTH Press, Aug 27, 2016 - History - 564 pages

And:

Proceedings of the International Conference on National Parks and Protected Areas, Kuala Lumpur, Malaysia, 13-15 November, 1989

Downloadable references: https://books.google.com/books?id=qJpJAAAAYAAJ&pg=PA70&dq=river+terrapin&hl=en&sa=X&ved=0ahUKEwjzsOWn1oPjAhXMop4KHeWFB1QQ6AEIRTAF#v=onepage&q=river%20terrapin&f=false

https://books.google.com/books?id=Nt1JAAAAYAAJ&pg=RA1-PA142&dq=river+terrapin&hl=en&sa=X&ved=0ahUKEwjzsOWn1oPjAhXMop4KHeWFB1QQ6AEIMDAB#v=onepage&q=river%20terrapin&f=false