In this type of contract, the elements are not specifically written or expressed. In fact, this type of contract is used as a remedy in a situation when one party to the quasi-agreement received unjust enrichment resulting from not paying for a product or service rendered.
A Drupe is a single fleshy fruit with a hard stone which contains the single seed. This is a Cherry (Prunus avium). Other fruits of this type are: Apricot (Prunus armeniaca), Plum (Prunus x domestica), Coconut (Cocos nucifera), Olive (Olea europaea), Peach (Prunus persica), Sloe (Prunus spinosa).
Japanese cherry (Prunus serrulata) in bloom. The genus Prunus includes the almond, apricot, cherry, peach and plum, all of which have cultivars developed for commercial fruit and nut production. The edible part of the almond is the seed; the almond fruit is a drupe, not a true nut. Many other species are occasionally cultivated or used for their seed and fruit.