148 Siti Sarah Binti Mohd Sinin 2019-01-18 https://www.researchgate.net/publication/304443423_Growth_and_yield_of_choy_sum_Brassica_chinensis_var_parachinensis_in_response_to_water_stress_and_nitrogen_fertilization_levels Kamarudin, K. N., Jaafar, H. Z., & Sung, C. T. B. (2012). Growth and yield of choy sum (Brassica chinensis var. parachinensis) in response to water stress and nitrogen fertilization levels. Conference: International Agriculture Congress 2012: Transforming Agriculture for Future Harvest, Putrajaya. DOI: 10.13140/RG.2.1.2126.2969 Revised record 29.8.2019