Artikel Jurnal
Nelson, Paul V.
Reston Publishing Company, Inc., 1985
Buku Teks
Sinaga, Apul Robyatno , author
Fakultas Teknik Universitas Indonesia, 2020
UI - Skripsi Membership
Tampion, John, author
GMC Publications, 1999
Buku Referensi
Wachidyah Anggraini, author
Fakultas Kesehatan Masyarakat Universitas Indonesia, 2012
UI - Skripsi Open