Charles Bukowski - American author

Can anybody recall any interaction (correspondence or otherwise) between the Buk & Burroughs?

I read in Sounes' biography that during a reading tour, where both Burroughs and Buk were reading, Burroughs cold-shouldered Buk and I don't know why this happened? Buk appeared to respect Burroughs, but there didn't seem to be any reciprocation.