Generalization of Haberdasher's Puzzle

In this paper, we scrutinize the Haberdasher's puzzle by Dudeney to produce equi-rotational pairs of figures systematically. We also generalize the puzzle by considering the tessellability condition (strong tessellability) for a pair of figures. As a result of it, it is shown that all pairs of strong tessellative and equi-rotational figures satisfy Conway criterion.