A search for Montville Harness's marriage record on FamilySearch indicated there were two references to he and Ella Boyer marrying in Canadian County, Oklahoma.
Both of these references indicate there was a marriage date.
The problem is that there was no marriage in 1901.
However, 151 pages later, in the entries for 1902, there is another entry for Harness and Boyer. This time they actually completed the marriage ceremony. A Methodist minister married the couple in Quincy, Oklahoma, in June of 1902.
FamilySearch.com makes it difficult to determine the specific letter of the volume from which these marriage record entries are taken. These images are taken from either volumes 4,5,or 6 from Canadian County, Oklahoma.