-. Tangga: Baja, kaca, besi, beton, kayu. Prima Infosarana Media.
Chicago Style (17th ed.) Citation-. Tangga: Baja, Kaca, Besi, Beton, Kayu. Prima Infosarana Media.
MLA (8th ed.) Citation-. Tangga: Baja, Kaca, Besi, Beton, Kayu. Prima Infosarana Media.
Warning: These citations may not always be 100% accurate.