Sourcer seems to generate a correct citation (and has more info like date accessed):
Benjamin was mentioned on a memorial in Christ Church Burial Ground, Philadelphia, Philadelphia County, Pennsylvania, United States with a death date of '''17 April 1790'''.<ref>
'''Memorial''':
"Find a Grave", database with images<br/>
{{FindAGrave|364}} (accessed 9 February 2024)<br/>
Memorial page for Benjamin Franklin (17 Jan 1706-17 Apr 1790), citing Christ Church Burial Ground, Philadelphia, Philadelphia County, Pennsylvania, USA (plot: Section A); Maintained by Find a Grave.<br/>
''"BENJAMIN<br>And<br>DEBORAH<br>FRANKLIN<br>1790"''.
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