Single-valuedness of the demand correspondence and strict convexity of preferences: An equivalence result

If preferences are rational and continuous, then strict convexity implies that the demand correspondence is single-valued (e.g. Barten and Böhm, 1982, lemma 7.3). We show that if, in addition, preferences are strictly monotone then the converse is also true, namely single-valuedness of the demand correspondence implies strict convexity of preferences.