The following publications are possibly variants of this publication:
- Flatwords and Post Correspondence ProblemTero Harju, Marjo Lipponen, Alexandru Mateescu. TCS, 161(1&2):93-108, 1996. [doi]
- On the n-permutation Post Correspondence ProblemMari Ernvall, Vesa Halava, Tero Harju. TCS, 601:15-20, 2015. [doi]
- Post Correspondence Problem for short wordsVesa Halava, Tero Harju, Mika Hirvensalo, Juhani Karhumäki. ipl, 108(3):115-118, 2008. [doi]
- Binary (generalized) Post Correspondence ProblemVesa Halava, Tero Harju, Mika Hirvensalo. TCS, 276(1-2):183-204, 2002. [doi]
- Remarks on Generalized Post Correspondence ProblemTero Harju, Juhani Karhumäki, Daniel Krob. STACS 1996: 39-48