Yearbooks can contain more than information on students and faculty. They sometimes contain advertisements like this one does from the Chicago, Illinois, area in 1925. This entry was obtained digitally in the of yearbook collection at Ancestry.com.
If you use an “index” to a record, do you consider how complete that index is? Is it an index to every name in the record, the “main names” in the record, or is there one index entry per record? The answers to those questions impact how you use the index. ——————- For those with an interest in United States records, here’s a post about those probate records on Ancestry.com. 
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