Helfer, J.W.

Helfer, J.W. 1859. Dr. Johann Wilhelm Helfer's gedruckte und ungedruckte Schriften uber die Tenasserim Provinzen, den Mergui Archipel und die Andamanen-Inseln. Mitttheilungen der Kaiserlich-Koniglichen Geographischen Gesellschaft zu Wien 3 (3): 260-275.

Helfer, J.W. 1839. The provinces of Ye, Tavoy and Mergue on the Tenasserim Coast: Visited and examined by order of Government, with the view to develop their natural resources. Calcutta, G.H. Huttmann.

Helfer, J.W. 1838. Notes on the animal productions of the Tenasserim Provinces. Journal of the Asiatic Society of Bengal 7 (2): 855-863.