The South African law of unjustified enrichment / Jacques du Plessis.

Basic features of the South African law of unjustified enrichment
The general requirements for liability based on unjustified enrichment
The enrichment arising from a transfer made to another or 'giving' : the conditiones
Enrichment arising from a transfer that failed to fulfil an obligation (the condictio indebiti)
Enrichment arising form a transfer that failed to achieve a future lawful purpose other than fulfilling an obligation (the condictio causa data causa non secuta)
Enrichment arising from a transfer made for illegal or immoral purpose (the condictio ob turpem vel iniustam causam)
Remaining cases of enrichment arising from a transfer (the conditio sine causa)
Enrichment imposed on another : general features of the category of claim
Enrichment imposed on another : unauthorised improvement of another's property
Enrichment imposed on another : unauthorised fulfilment of another's obligation
Enrichment by taking from another or infringement of another's rights : general features of the category of claim
Enrichment by taking from another or infringement of another's rights : specific cases.