Cistercian numerals (English Wikipedia)

Chrisomalis, Stephen (2010). Numerical notation : a comparative history. Cambridge: Cambridge University Press. p. 350. doi:10.1017/CBO9780511676062. ISBN 978-0-511-67683-3. OCLC 630115876.
King, David A. (1992). "The Ciphers of the Monks and the Astrolabe of Berselius Reconsidered". In Demidov, Sergei S.; Rowe, David; Folkerts, Menso & Scriba, Christoph J. (eds.). Amphora. Basel: Birkhäuser. pp. 375–388. doi:10.1007/978-3-0348-8599-7_18. ISBN 978-3-0348-8599-7.
Meskens, Ad; Bonte, Germain; De Groot, Jacques; De Jonghe, Mieke & King, David A. (1999). "Wine-Gauging at Damme [The evidence of a late medieval manuscript]". Histoire & Mesure. 14 (1): 51–77. doi:10.3406/hism.1999.1501.
Beaujouan, Guy (1950). "Les soi-disant chiffres grecs ou chaldéens (XIIe – XVIe siècle)". Revue d'histoire des sciences (in French). 3 (2): 170–174. doi:10.3406/rhs.1950.2795.
Moyer, Ann (2003). "Book review". Speculum. 78 (3): 919–921. doi:10.1017/S0038713400132002. JSTOR 20060835. Retrieved 2021-01-08.

formulae.org (Global: low place; English: low place)

R.Ugalde, Laurence. "Cistercian numerals in Fōrmulæ programming language". Fōrmulæ. Retrieved July 29, 2021.

Moyer, Ann (2003). "Book review". Speculum. 78 (3): 919–921. doi:10.1017/S0038713400132002. JSTOR 20060835. Retrieved 2021-01-08.
Spalt, Detlef (2004). "Book review". Sudhoffs Archiv (in German). 88 (1): 108–109. JSTOR 20777934. Retrieved 2021-01-08.

Meskens, Ad; Bonte, Germain; De Groot, Jacques; De Jonghe, Mieke & King, David A. (1999). "Wine-Gauging at Damme [The evidence of a late medieval manuscript]". Histoire & Mesure. 14 (1): 51–77. doi:10.3406/hism.1999.1501.
Beaujouan, Guy (1950). "Les soi-disant chiffres grecs ou chaldéens (XIIe – XVIe siècle)". Revue d'histoire des sciences (in French). 3 (2): 170–174. doi:10.3406/rhs.1950.2795.

Chrisomalis, Stephen (2010). Numerical notation : a comparative history. Cambridge: Cambridge University Press. p. 350. doi:10.1017/CBO9780511676062. ISBN 978-0-511-67683-3. OCLC 630115876.
King, David A. (2001). The Ciphers of the Monks : a forgotten number-notation of the Middle Ages. Stuttgart: F. Steiner. pp. 16, 29, 34, 41. ISBN 3-515-07640-9. OCLC 48254993.
Sesiano, Jacques (1985). "Un système artificiel de numérotation au Moyen Age". In Folkerts, Menso & Lindgren, Uta (eds.). Mathemata : Festschrift für Helmuth Gericke (in French). Stuttgart: F. Steiner Verlag. ISBN 3-515-04324-1. OCLC 12644728.