[1] C. Aebi and G. Cairns, Lattice equable quadrilaterals I: Parallelograms, Enseign. Math., 67 no. 3-4 (2021) 369–401.
[2] C. Aebi and G. Cairns, Lattice equable quadrilaterals II: kites, trapezoids and cyclic quadrilaterals, Int. J. Geom., 11 no. 2 (2022) 5–27.
[3] C. Aebi and G. Cairns, Equable parallelograms on the Eisenstein lattice, Math. Slovaca, 74 no. 4 (2024) 963–982.
[4] C. Aebi and G. Cairns, Equable triangles on the Eisenstein lattice, to appear in the March 2025 issue of Math. Gazette., Preprint available at
https://arxiv.org/abs/2309.04476.
[5] C. Aebi and G. Cairns, Less than equable triangles on the Eisenstein lattice, to appear in the July 2025 issue of Math. Gazette., Preprint available at https://arxiv.org/abs/2312.10866.
[6] C. J. Bradley, Challenges in geometry, For Mathematical Olympians past and present, Oxford University Press, Oxford, 2005.
[7] A. Ostermann and G. Wanner, Geometry by its history, Springer, Heidelberg, 2012.
[8] N. J. A. Sloane, The on-line encyclopedia of integer sequences, https:\oeis.org.
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