Parveen. “An Analysis Of Long-Term Crop Combination In NorthWestern Haryana Using Doi’s Crop Combination Statistical Method (1990-91 & 2021-22)”. Elementary Education Online, vol. 20, no. 6, Dec. 2023, pp. 4828-36, https://ilkogretim-online.org/index.php/pub/article/view/4281.