Janzen Charcoal Pencil Print Poster 1980 Native American Woman Michael David ?

I don't know much/remember about this item. I was an exchange student in Russia in 1991-1992 & was an acquaintance of the artist's son. He told me about his father being an artist (California) & gifted this to me. If I remember correctly the son was a Jr., so this would be by Michael Janzen, but, also the name David is in my head as well. The son's name was definitely Michael Janzen.
This is an approximately 20" tall x 16" wide print (thicker "sketch paper" stock) of what I believe is a Native American Woman, dated 1980 (I don't know the proper name/title of this work). It appears to be a charcoal/pencil print, but I'm not an authority. This has seen some life/wear. There is discoloration starting the center of the poster and other flaws, pictured. I have carried this with me for many years and think it is time to be with someone that will care for and appreciate it.