Using results of drop list to populate cell

Hi all,
After a bit of help on a formula! I am trying to create a rota for a hospital charity, I have fields for nurses, clinics & days they are open.
The head nurse needs to input the nurses to cover the clinics, the problem I have I'd this:

In a cell the head nurse selects a clinic from a drop down list for example ear clinic, so nurse a is due to work in a ear clinic on a Monday,
In a seperate spreadsheet I am wanting the formula to show that if clinic ear has been selected (cell a1) for nurse a (cell a2 ) then cell a3 shows the nurses name. Essentially if the nurse has been asked to work in a clinic from a list then I need to let the clinc know that this nurse has been allocated , as there is a number of clinics in the list the results will vary on what nurse is covering what clinic.

Hope this makes sense