This set of three DC Superman comic books includes issues #173, #233, and #426, all from the Sliver and Bronze Age eras.  

Book # 173 is a 1964 year, featuring " The Triumph of Luthor and Brainiac!"  Cover has good glossy color with some rash on spine, lower right corner has a bend and slight wave.  First page is ripped along top, pages are off white to white, back page also has slight rash along spine but good glossy color.  For age its a survivor.  (see pics)

Book # 233 is a 1971 year, "Kryptonite Nevermore!", Cover has good glossy color, pages are off white to white, this is a nice mid-grade book.

Book # 426, is 1973 Action Comic featuring Super-man, Green-Arrow, and The Human Target.  Cover has good glossy color, spine has waved to the left, pages are off white to white, back cover good glossy color, if not for the spine wave this would be a solid mid-grade book.  (see pics)