OBITUARY INFORMATION FROM FIND-A-GRAVE WEBSITE:

Otto William Hartman
BIRTH          22 Nov 1945
DEATH          8 Oct 1983 (aged 37)
BURIAL         Calvary Cemetery, Portage, Porter County, Indiana, USA
PLOT           I-23
MEMORIAL ID    60893598

This information and the picture below were obtained from: https://www.findagrave.com/memorial/60893598/otto-william-hartman.  The picture above was obtained from the 1964 HHS Memories yearbook, made available by the Lake County Public Library, at: https://archive.org/details/HOHS1964Images/.