MUJAHID, A M, and A J GUPTA. “Effect of Plant Spacing, Organic Manures and Inorganic Fertilizers and Their Combinations on Growth, Yield and Quality of Lettuce (Lactuca sativa)*”. The Indian Journal of Agricultural Sciences, vol. 80, no. 2, Jan. 2011, https://doi.org/10.56093/ijas.v80i2.2867.