Names Of Sheets

[fairyrak]

hi, I have an excel file with a great amount of sheets and the sheets all have different strange and long names but I just want to sum the values of (L17+M17+M18) of all the sheets and that's all, the same 3 cells for each sheet
what's the formula to sum those 3 cells of every sheet withouth having to write lots and lots of names of sheets?

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another problem, luckily I have all the names of all the sheets in the column A of one more new sheet as follows

nameofthesheet1 (this thing written in A1)
nameofthesheet2 (this thing is written in A2)
nameofthesheetorwhatevername (this thing is written in A3)


If I drag down the formula of B1 nameofthesheet1!L17 to B2 it will put the formula: nameofthesheet1!M17, but I hate that because what i want it to become is something like nameofsheet(textofA2))!L17 so what do I have to write in B1? so that i can drag and drop to B2 and to B3 and in one second fill the column B with all what i want?

(I know that L$17 will make half of my job but i need the first part of the formula too, the first part is is nameofthesheet!

[fairyrak]

note (I want to sum the cells L17+M17+M18 of sheet 1 + the cells of sheet 2 L17+M17+M18 and so on)

[Fibonacci]

These should help:

http://www.artifax.net/excel/excel-tips-how-to-add-together-the-same-cell-on-multiple-worksheets/

http://www.notjustnumbers.co.uk/2014/05/excel-tip-adding-same-cell-across.html