College algebra and trigonometry /gustafson r david roy david 1936著
Essential mathematics with geometry /gustafson r david roy david 1936著
Algebra for college students /gustafson r david roy david 1936著
College algebra /gustafson r david roy david 1936著
Concepts of intermediate algebra : an early functions approach /gustafson r david roy david 1936著
Elementary geometry /gustafson r david roy david 1936著