Insert formula within quotations referencing a different sheet.

I have a sheet for every day of the month that feeds into a central sheet so that the data is easier to work with. Each row is associated with a date in "MM/DD/YY" format in the central sheet and the name of each sheet associated with a day of the month is simply 1 through 31. The same cell is referenced from each of the day sheets. I tried to use ='DAY(B12)'!$H$8 but it throws a reference error. Is there any way for DAY(B12) to calculate its value to be used for sheet reference within the parentheses?