ITC Serif Gothic in U&lc, Vol. 1 No. 2, 1974
Source: http://uandlc.com.U&lc Magazine. License: All Rights Reserved.
ITC Serif Gothicwas released in 1972. The second issue of U&lc announces four new weights for the family (Light, Extra Bold, Heavy, and Black) and uses the typeface liberally, particularly the new heavy stuff.
Source: http://uandlc.com.U&lc Magazine. License: All Rights Reserved.
Source: http://uandlc.com.U&lc Magazine. License: All Rights Reserved.
Unfortunately the pages from this report on ATypI 1973 were overcropped in Monotype's scan. If anyone has a better image, please tell us.
Source: http://uandlc.com.U&lc Magazine. License: All Rights Reserved.
Source: http://uandlc.com.U&lc Magazine. License: All Rights Reserved.
Unfortunately this page announcing ITC Serif Gothic's new weights was overcropped in Monotype's scan. If anyone has a better image, please tell us.