Robert A. Morris, Lina Khatib. An interval-based temporal relational calculus for events with gaps. J. Exp. Theor. Artif. Intell., 3(2):87-107, 1991. [doi]
@article{MorrisK91,
title = {An interval-based temporal relational calculus for events with gaps},
author = {Robert A. Morris and Lina Khatib},
year = {1991},
doi = {10.1080/09528139108915283},
url = {http://dx.doi.org/10.1080/09528139108915283},
researchr = {https://researchr.org/publication/MorrisK91},
cites = {0},
citedby = {0},
journal = {J. Exp. Theor. Artif. Intell.},
volume = {3},
number = {2},
pages = {87-107},
}