Wongpiyasatid, A. . and Hormchan, P. . (2001) “Comparison of the Single and Double Flowered Portulaca Varieties in Bee Attraction”, Agriculture and Natural Resources. Bangkok, Thailand, 35(1), pp. 8–13. Available at: https://li01.tci-thaijo.org/index.php/anres/article/view/240314 (Accessed: 3 May 2024).