Singhal, R. M., and S. Soni. “Spectral Properties and Colloidal Rehaviour of the Humic Acids of the Soils under Oak (<I>Quercus incana< I>), Dfodar (<I>Cedrus deodara< I>) and Chik (<I>Pinus roxburghii< I>) of Mussoorie Himalayas (U.P.)”. Indian Forester 113, no. 10 (October 1, 1987): 684–690. Accessed July 10, 2025. https://indianforester.co.in/index.php/indianforester/article/view/9466.