Singh, S K, P K Singh, K K Singh, K N Shukla, and H S Chauhan. “Development of a Wetting Front Indicator for the Measurement of Sub-Surface Wetted Front Advance”. Journal of Agricultural Engineering 37, no. 4 (December 5, 2006). Accessed June 6, 2026. https://epubs.icar.org.in/index.php/JAE/article/view/14097.