
“This is not a novel to be tossed aside lightly. It should be thrown with great force.”
Quoted in The Algonquin Wits (1968) edited by Robert E. Drennan, and The Dispatch http://news.google.com/newspapers?id=r04cAAAAIBAJ&sjid=WFEEAAAAIBAJ&pg=7250,5269688&dq=aside-lightly+dorothy-parker&hl=en (October 1962). As noted at Snopes, Drennan's source seems to be a Parker review which does not seem to contain this quote. If Parker wrote this statement anywhere the primary source seems to have gone missing.
The earliest attribution of this quote was published in the February 1960 Readers' Digest, and credited to a book review by Sid Ziff in the Los Angeles Mirror-News, which existed from 1955 to 1960. This is a little odd, considering that Sid Ziff was a sports columnist; the reference in Readers' Digest has been confirmed but the quote from the Mirror-News has not - see Quote Investigator http://quoteinvestigator.com/2013/03/26/great-force/#more-5787 for details.
Misattributed