All examples here fit left in BP809, a version where the figures are allowed to pass through themselves while being deformed.
Adjacent-numbered pages: BP805 BP806 BP807 BP808 BP809  *  BP811 BP812 BP813 BP814 BP815
nice, math, unorderedpair, traditional
two_homeomorphic_figures_made_of_curves [smaller | same | bigger]
Aaron David Fairbanks