I have Lucifer's Hammer, just started reading it, dated but also contemporary !
Both Armegeddon and the much better Deep Impact have passing references to "you mean like Lucifer's Hammer?" in the dialog. I may not make it into the "edited for TV version but it was there in both movies in the original versions. They knew who they were ripping off (and who had done it better).
If you like apocalypse books try "Earth Abides" by George R. Stewart.