Gaya APA

manual of biology. ([s.a.]). Amerika: [s.n.].

Gaya Chicago

manual of biology. . Amerika: [s.n.], [s.a.]. Text.

Gaya MLA

manual of biology. . Amerika: [s.n.], [s.a.]. Text.

Gaya Turabian

manual of biology. Amerika: [s.n.], [s.a.]. Print.