where do you find what paper work to file?

"You do not need to file an application for the lump-sum as a widow(er) if you were entitled to wife's or husband's benefits on the deceased person's Social Security record for the month just before the month in which the insured person died."

how do you find out if you do not need to file? wife got her soc sec because of my earnings. she never worked enough quarters.

Hopefully, this could be handled over phone or web or mail.. vs trip into soc sec office.