If reference citation in the text names a discussant specifically rather than the author(s), eg, “as noted by Easter,1” the following form is used (see also 3.13.10, Special Print Materials, Secondary Citations and Quotations [Including Press Releases]).
1. Easter DW. In discussion of: Farley DR, Greenlee SM, Larson DR, Harrington JR. Double-blind, prospective, randomized study of warmed humidified carbon dioxide insufflation vs standard carbon dioxide for patients undergoing laparoscopic cholecystectomy. Arch Surg. 2004;139(7): 739–744.