Gaya APA
Johnston, C.
(1970).
Plane trigometry : a new approcah
(
2th.ed.)
.
Englewood Cliffs:
Prentice-Hall.
Gaya MLA
Johnston, C.L..
"Plane trigometry : a new approcah".
2th.ed.
Englewood Cliffs:
Prentice-Hall,
1970.
Text.