procedure QUAD3D(XX1, XX2:real; var SS:real);
begin
    QGAUSX(XX1, XX2, SS);
end;

Function F(ZZ:real):real;
begin
    Z := ZZ;
    F := FUNC(X, Y, Z);
end;

Function G(YY:real):real;
var
    B1,B2,SS:real;
begin
    Y := YY;
    B1 := Z1(X, Y);
    B2 := Z2(X, Y);
    QGAUSZ(B1, B2, SS);
    G := SS;
end;

Function H(XX:real):real;
var
    A1,A2,SS:real;
begin
    X := XX;
    A1 := Y1(X);
    A2 := Y2(X);
    QGAUSY(A1, A2, SS);
    H := SS;
end;