Subject: Sign conventions Date: Wed, 12 Jun 2002 15:24:08 +0200 (MET DST) From: David J Green To: Don Davis Milnor in his classic paper on the Steenrod algebra and its dual (published Jan 1958, submitted May 1957) explicitly states the now-current sign convention for interchanging any two objects which can be assigned dimensions. He cites the formula for the relationship between the homology cross product and the cohomology cross product as an example of where the sign convention contradicts the "usual usage". David Green.