Copyright help?

In prowling for epigraphs for Kingdoms, I found "Dust", by Dorothy Anderson. I'm quite smitten, but I'm having a hell of time getting any information on her out of Google. It was apparently published in the Anthology of Magazine Verse for 1920 (William Stanley Braithwaite, ed.), but that's all I have.

Is anyone familiar with Dorothy Anderson, or know where I should look for more information?

My other favorite so far is Carl Sandburg's "Troths", which is too short for two lines fair use. At least I have contact information for his estate.