Duplicate text values
 

I have multiple worksheets (Jan-Dec) where a text value has been entered in a
column (col A) that includes blank cells. I need to look at all the text
values in col A, worksheets Jan-Dec, come up with a list of unique text
values and create a list in a separate worksheet. Is this even possible? I
cannot find a formula that will work with text.
Thanks in advance for any assistance!