(Left) Redshift vs. apparent r-band magnitude plot. Red open circles show the redshift by SDSS DR16, and black filled circles show the measurements in this study. Background shows a number contour of all SDSS DR16 galaxies (photometric type = GALAXY) with spectroscopic redshift in 0 < r < 18 and 0.002 < z < 0.35. Green open rectangles show outliers. (right) SDSS DR16 finding charts around the outliers in the left panel.