APA Style

Dhawan, D. (2020 (approximate; p). Problems in Optics (Latest edition (please confirm if you have a speci). : New Delhi, India: S. Chand Publishing.

MLA Style

Dhawan, D.K.. "Problems in Optics". Latest edition (please confirm if you have a speci : New Delhi, India: S. Chand Publishing, 2020 (approximate; p. Text.