IDRIS, Ts. Mohd Safiee. MODUL OPERASI KENDIRI SIRI 1. [s.l.] : Penerbit UTHM,2021. Disponível em: https://penerbit.uthm.edu.my/omp/index.php/penerbituthm/catalog/book/303.. Acesso em: 18 jul. 2024.