Impact Factor
4.81
Estimated influence, citation density, publishing volume, and citation integrity from the analytics table.
Volume, recency, access pattern, and citing-community signals from the journal analytics record.
Recent article records with DOI-first linking and condensed abstracts.
Last issue of each vol. is the annual summary of statistics for the proceding calendar year.
Ceased in print with Vol. 63, no. 29 (Jul. 2014).
Also issued online.
v. 25, no. 10 (Mar. 19, 1976)-Will not microfilm 20040413
19950523 Not printed on acid-free paper