Journal Article
Walangitan, Hengki D, Budi Setiawan, Bambang Tri Raharjo, and Bobby Polii.
"Optimization of Land Use and Allocation to Ensure Sustainable Agriculture in the Catchment Area of Lake Tondano, Minahasa, North Sulawesi, Indonesia." International Journal of Civil \& Environmental Engineering 12, no. 3 (2012): 68-75.