N. Z. Zahari and P. M. Tuah, “Formulation and Viability of Consortia LIBeM Using Protective Agent Skim Milk Subjected to Freeze Drying Method for Degradation of Oil Sludge Contaminated Soil”, J Environ Microbiol Toxicol, vol. 7, no. 2, pp. 14–19, Dec. 2019.