Hi, i have

if A1=John

sheet 1 sheet 2 sheet 3 ....etc
A1=John A1=John A1=John
B2=00:01:29 B2=00:08:41 B2=00:24:04

I need the sum of all the cells corespondent to John
But John is not in every sheet, and i have 31 sheets.
Can this be done?