Discrete Mathematics:

If each of \(X\) and \(Y\) is a person, then the relation \(X < Y\) indicates that the notes originated with \(Y\) and were subsequently modified by \(X\text{,}\) who takes full responsibility for the current version. While \(Y\) is credited with the genesis of the notes, s/he makes no claim to the accuracy of the current version which may or may not reflect her/his original version.