adding same cell on multiple sheets

Hello again,

I have 52 sheets (for each week in the year) labeled by their respective number that contain sums of hours. I'd like to add the sums for each category across all sheets. Each category's total would be found in the same cell (i.e. '21'!e5,'22'e5,'23'e5, etc).

Is there a less cumbersome way of adding the same cell from 52 sheets together than manually referencing each individual cell 52 times per category, for several categories?

THanks

tRY something like:

=SUM('1:52'!E5)