Apriandi, N., Y. D. Herlambang, T. Prasetyo, M. Margana, K. M. T. Negara, and R. Raharjanti. “Theoretical Study of The Determination of Optimal Tilt Angle of a Solar Collector Case Study: Mataram – Nusa Tenggara Barat”. Jurnal Ilmiah Rekayasa Pertanian Dan Biosistem, vol. 11, no. 2, Sept. 2023, pp. 281-9, doi:10.29303/jrpb.v11i2.416.