This document from 1980 contains two featured articles strongly attacking the 1980 Libertarian Party presidential campaign of Ed Clark and David Koch.
The first article, titled, “The Clark Campaign: Never Again,” argued that “the Clark campaign was a fourfold disaster, on the following counts: betrayal of principle; failure to educate or build cadre; fiscal irresponsibility; and lack of votes.” The article mocked David Koch for only garnering 1% of the vote after spending $2 million of his own money on the campaign, and also joked that “for a measly $2 billion of his personal fortune, David could buy us victory in 1984!”
In the second article, David Nolan argued that “One more campaign like this will, quite literally, kill the party; nobody in his right mind will stick around for another round of lies, abuse, and betrayal of principle like the one Ed Crane engineered in 1980.”
For analysis of this document, see the 2014 article by Daniel Schulman in Mother Jones titled, “Late Libertarian Icon Murray Rothbard on Charles Koch: He “Considers Himself Above the Law.”