"The question of the value of Hayek’s work in technical economic theory from the middle 1920s through early 1940s is one over which there is considerable dispute in the academic economic community. Some, such as contemporary Austrian economists Roger Garrison, Mark Skousen, and Gene Callahan, consider this work to be of vital, continuing relevance. Others, such as Nobel Prize winners Milton Friedman, James Buchanan, and Ronald Coase, while they have the highest opinion of Hayek, do not consider his work in technical economic theory to be of much worth."