The Polar Cap (PC) index is a controversial topic within the IAGA scientific community. Since 1997 discussions of the validity of the index to be endorsed as an official IAGA index have ensued. The article: "The PC index: review of methods", written by two members of the IAGA PC index committee, H. McCreadie and M. Menvielle, holds a critical review of some aspects of the methods used to derive PC index values. However, a number of incorrect statements and factual errors have been found and

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... l be called attention to and discussed in this commentary. Further critical comments concern the Corrigendum issued by the same authors and published in Ann. Geophys., 29, 813-814, 2011.