Nucifera, F. et al. 2020. Estimation green space in Yogyakarta City in the year of 2002-2019 using NDVI approach. Geo Media: Majalah Ilmiah dan Informasi Kegeografian. 18, 2 (Nov. 2020), 97–105. DOI:https://doi.org/10.21831/gm.v18i2.34713.