WEN KAM LEONG; ALEX LUNG KEAT NGO; ALVIN CHOON HSIEN WONG; JEN HUA LING; HOW TECK SIA. The Mandatory 4 Years Desludging Frequency of Underground Septic Tanks in Residential Areas: A Case Study in Sibu Sarawak, East Malaysia. Journal of the Civil Engineering Forum, v. 8, n. 2, p. 147-156, 25 May 2022.