quality:corruption
Notation

Different authors use different notations for the Cauchy principal value of a function f {\displaystyle f}, among others:

as well as P, {\displaystyle P,} P.V., P, {\displaystyle {\mathcal {P}},} P v, {\displaystyle P_{v},} (C P V), {\displaystyle (CPV),} and V.P.