I answered when they called. Nobody on the line. So, I called them. On their automated menu, there was a choice to find out the purpose of their call. Said they "represent hundreds of magazine publishers" and were calling to update their files.

There was no one on the line when I answered too.  I called back, got the same automated message (represent 100s of magazines).  If you press 3, it will remove you from the calling list.  After pressing 3, there are more prompts--to remove the # you are calling from or to remove another #.