APA Style

Samuelson, Paul A, Nordhaus, William D, Sumaryati, Margaretha, Gretta. (). . : .

Chicago Style

Samuelson, Paul A, Nordhaus, William D, Sumaryati, Margaretha, Gretta. . : , . .

MLA Style

Samuelson, Paul A, Nordhaus, William D, Sumaryati, Margaretha, Gretta. . : , . .

Turabian Style

Samuelson, Paul A, Nordhaus, William D, Sumaryati, Margaretha, Gretta. . : , . .