List if?????

Hi I was looking for a bit of help if at all possible.

I have on one worksheet 5 individual names (cell ref, c26,c36,c46,c56,c66) which only appear if certain criteria are met on a previous worksheet, and will always appear specifically in those cells.

What I need is some kind of formula that will allow me on a 3rd spreadsheet to list (in cells a1:a5) which of the 5 names are present from the previous sheet. Sounds simple eniugh right?

However, I need the formula to be dynamic so that if only 3 names are present it will only populate cells a1:a3, and if the only name present is the name in c66, this would appear in a1 etc..

Anybody got any ideas????