• Pentamino IVõhandu, LeoHorisont1975 / lk. 42 : ill https://www.ester.ee/record=b1072243*est https://www.digar.ee/viewer/et/nlib-digar:291320/261878/page/38
• Pentamino IIVõhandu, LeoHorisont1975 / lk. 42 : ill https://www.ester.ee/record=b1072243*est https://www.digar.ee/viewer/et/nlib-digar:291321/261882/page/39