Lyrics question

[Karl Hiller]

OK, so, I'm reading one of the new Chaosium Cthulhu fiction anthologies,
and there's a story by Karl Edward Wagner titled "The River of Night's
Dreaming."

This sounds very familiar, but I can't place it.  I'm almost convinced
that it's from a song...  There is another story by Robert Chambers
titled "The King in Yellow", which of course was used in a BOC lyric, and
I'm wondering if "the river of night's dreaming" sounds familiar because
it was used in a BOC song.

Any help?

Karl