Patents for inventions abridgment of specification 3000 - 35000 - Govt. of India PaPatent office (Delhi : Govt. Press, 1957)
Group II. - Sanitation (1) Closets, baths and like sanitari applicances.(2) Drains and Sewers.(3)Sewage, treatment of.(4)Water and unspecificafied liquids, purifying and sottenry.