Willems J
Acta Anaesthesiol Belg. 1976;27(3):85-8.
According to the classical receptor occupancy theory non-depolarizing and depolarizing muscle relaxants differ in one respect: both types of drugs possess affinity for the cholinergic receptor at the neuro-muscular function, but only the depolarizing relaxants show efficacy. The two properties, affinity and efficacy are independent from each other.