Zakaria, Zarina, Alina Rahayu Mohamed, Noor Hasyierah Mohd Salleh, and Siti Nursheela Abu Mansor. 2013. “Total Nitorgen Content from Earthworm (Eisenia Foetida) Using The Kjeldahl Method”. IIUM Engineering Journal 14 (1). https://doi.org/10.31436/iiumej.v14i1.315.