APA-viite

Martens, H. R. (1969). Introduction to systems theory. Charles E Merrill.

Chicago-tyylinen lähdeviittaus

Martens, Hinrich R. Introduction to Systems Theory. U S A: Charles E Merrill, 1969.

MLA-viite

Martens, Hinrich R. Introduction to Systems Theory. Charles E Merrill, 1969.