[…] The method of arranging the morphemes of a language consists of three steps: 1. dividing each phonemically written linguistic expression into the smallest parts which recur with the same meaning in different expressions, each such part to be called a morpheme alternant; 2. grouping into a distinct morpheme unit all alternants which satisfy the following conditions: (a) have the same meaning (b) never occur in identical environments, and (c) have combined environments no greater than the environemnts of some single alternant in the language; 3. making general statements for all units which have identical difference between their alternants.
- Harris (1942a), Pag. 179