Plane curves of the eighth order : with two real four-fold points having distinct tangents and with no other point singularities
A doctoral dissertation in analytic plane geometry by Elizabeth Buchanan Cowley, printed in Lancaster, Pennsylvania, in 1908 for mathematicians studying the classification of octic curves. Its numbered line plates show looping eighth-order curves with two four-fold crossing points, drawn in solid, dotted, and dashed strokes against cream paper, giving designers a stock of ribbon-like knots, asymptote lines, and figure-eight loops.
