Walter Wilson Greg
（1927年刊行，Clarendon Press, Oxford, vii+63 pp.／Reprinted in 1971: Folcroft Library Editions → 書評｜目次｜情報）
【目次】
Preface v
General notions: Descent and variation 1
Recording variants 14
Types of variants 18
Principles of variation 21
Resolurion of variants 30
Method and limitatations of the calculus 43
Note A —— On collateral groups 55
Note B —— On conflation 56
Note C —— On some common errors 58
Diagrams of typical families 60
Index 62
