1. Hearn, R.A., Demaine, E.D.: Games, Puzzles, and Computation. A.K. Peters, Natick (2009)
2. Andersson, D.: Hashiwokakero is NP-complete. Inf. Process. Lett. 109(19), 1145–1146 (2009)
3. Kölker, J.: Kurodoko is NP-complete. J. Inf. Process. 20(3), 694–706 (2012)
4. Takenaga, Y., Aoyagi, S., Iwata, S., Kasai, T.: Shikaku and Ripple Effect are NP-complete. Congressus Numerantium 216, 119–127 (2013)
5. Ishibashi, A., Sato, Y., Iwata, S.: NP-completeness of two pencil puzzles: Yajilin and Country Road. Util. Math. 88, 237–246 (2012)