@misc{oai:tsukuba.repo.nii.ac.jp:02000401,
 author = {Fajar, Setiawan},
 month = {},
 note = {2020, 【要旨】},
 title = {Long-Term Change of the Secchi Disk Depth in Indonesian Lakes Shown by Landsat TM and ETM+ Data},
 year = {2021}
}