Ludwig Von Mises
Human aAction - Part Four, Chapter XVI. Prices, §§ 8-15
Summary:
In the same way in which governments restrict competition in order to improve the position of privileged sellers, they can also restrict competition for the benefit of privileged buyers. Again and again governments have put an embargo on the export of certain commodities. Thus by excluding foreign buyers they have aimed at lowering the domestic price. But such a lower price is not a counterpart of monopoly prices.
What is commonly dealt with as monopoly of demand are certain phenomena of the determination of prices for specific complementary factors of production.