Sparks, Fred W. Rees, Paul K.
Plane trignometry - 4th ed. - Englewood Cliffs Prentice Hall 1960 - x, 76p. : ill.
514.1/.5 / S7
Plane trignometry - 4th ed. - Englewood Cliffs Prentice Hall 1960 - x, 76p. : ill.
514.1/.5 / S7