From the introduction: "Being somewhat familiar with Longacre's case grammar approach to clause analysis, (Longacre, 1974), I felt it would be helpful to apply his sentence level techniques to the study of Choctaw. Longacre presents a binary, eight-part framework within which he groups all the various types of sentence combinations. [...] I chose to concentrate on the first four deep structures which find their counterparts in formal logic. Basically, conjoining and alternation are non-sequential deep structures while temporal and implication are sequential."
Swartz, Stephen M.
"Some Choctaw sentence structures,"
Work Papers of the Summer Institute of Linguistics, University of North Dakota Session: Vol. 18, Article 10.
Available at: https://commons.und.edu/sil-work-papers/vol18/iss1/10