Indirect reference to changing worksheet name

I am trying to reference a cell in another worksheet. I have a master worksheet and three other worksheets named Budget 1, Budget 2 and Budget 3. In the master worksheet I have a cell, say B3, with the Budget worksheet number. I then want to access cell C5 in worksheet "Budget (B3 ref). Hope this makes sense - attached copy of test workbook.
I know there are a lot of post on the Indirect function, but have had trouble figuring it out.
Many thanks.

Try:

=INDIRECT("'Budget "&B3&"'!C5")

Thank you - got there once I worked out where the double quotes were and the single quote.