This article has been discussed numerous times, here’s some links for some of the past discussions:
https://forum.freecapitalists.org/t/refutations-of-the-austrian-business-cycle-austrian-economics/12215/7
https://forum.freecapitalists.org/t/some-critiques-of-austrian-economics-for-those-in-the-mood-to-dissect-them/252/7
https://forum.freecapitalists.org/t/does-rothbard-contradict-himself-with-regards-to-the-law-of-diminishing-marginal-utility/14231/6
https://forum.freecapitalists.org/t/any-rebuttals-to-critiques-of-austrian-economics/2653/8
Hope that helps.