I found the following on my great grandparent's graves:
Name, 1863-1937, followed by:

FOA No4 DOH No494 on GreatGrandpa's.

GreatGrandma has 1870-1933 followed by:

ODF No4.

Anyone have any idea what these mean? No other crypts in same mausoleum have these inscriptions. No one at the cemetery had any idea.