TY - JOUR T1 - The theory of classification part 9: Inheritance and self-reference JO - Journal of Object Technology UR - https://eprints.whiterose.ac.uk/79274/ PY - 2003/01/01 AU - Simons AJH ED - DO - DOI: 10.5381/jot.2003.2.6.c2 VL - 2 IS - 6 SP - 25 EP - 34 Y2 - 2025/07/04 ER -