Abdul Halim, S. N. B., A. A. Harum, M. A. Jamaludin, and B. K. Muflih. “Muslim-Friendly Railway Services: Concept and Challenges of Malaysian Electric Train Service (ETS)”. Journal of Halal Industry & Services, vol. 3, no. 1, June 2020, doi:10.36877/jhis.a0000094.