WALLLLLACE, A. Langkah-langkah hijau. Yayasan Obor Indonesia.
Chicago Style (17th ed.) CitationWALLLLLACE, AUBREY. Langkah-langkah Hijau. Yayasan Obor Indonesia.
MLA (8th ed.) CitationWALLLLLACE, AUBREY. Langkah-langkah Hijau. Yayasan Obor Indonesia.
Warning: These citations may not always be 100% accurate.