If you populate column A on sheet1 with countries (so A6:A9=France,A10:A13=Germany), than you can use: =INDEX(INDIRECT(A6&"!$C$6:$C$17"),SUMPRODUCT((INDIRECT(A6&"!$A$6:$A$17")=$C$3)*(INDIRECT(A6&"!$B$6:$B$17")=B6)*(ROW($1:$12))))

If you don't want to populate column A and keep just 1st field (so A7:A9 and A11:A13 are empty), it's still possible, but the formula will look like this:

=INDEX(INDIRECT(INDEX($A$6:$A$13,SUMPRODUCT(MAX(ISTEXT($A$6:A6)*ROW($1:1))))&"!$C$6:$C$17"),SUMPRODUCT((INDIRECT(INDEX($A$6:$A$13,SUMPRODUCT(MAX(ISTEXT($A$6:A6)*ROW($1:1))))&"!$A$6:$A$17")=$C$3)*(INDIRECT(INDEX($A$6:$A$13,SUMPRODUCT(MAX(ISTEXT($A$6:A6)*ROW($1:1))))&"!$B$6:$B$17")=B6)*(ROW($A$1:$A$12))))

confirmed by ctrl-shift-enter