I almost found something here, but not exactly what I need.

I have 20 sheets named (tabbed) after different cities (let's say starts
with "SHA", ends with "SYD"). Their row 10 (from column F to Z) contains when
the sales happens (2008,2009 etc, BUT each has a different start). Row 12
(from column F to Z) has the corresponding sales amount.

I also have a total sheet and in the total sheet I need to sum up the sales
of all the cities by year (from column F=2008 to column Z=2028).

I find a fomula he
=SUM(SUMIF(INDIRECT("Sheet"&{1,2,3}&"!A:A"),"EU",I NDIRECT("Sheet"&{1,2,3}&"!C:C"))).
The only problem is I have 20 sheets and I tried to use "SHA:SYD!F10:Z10" to
replace "Sheet"&{1,2,3}&"!C:C" but it doesn't work. Any idea? Thanks!