Joseph P. Loyall, Simon M. Kaplan. Visual concurrent programming with Δ-grammars. Journal of Computer Languages, 3(2):107-133, 1992. [doi]
@article{LoyallK92,
title = {Visual concurrent programming with Δ-grammars},
author = {Joseph P. Loyall and Simon M. Kaplan},
year = {1992},
doi = {10.1016/1045-926X(92)90012-B},
url = {http://dx.doi.org/10.1016/1045-926X(92)90012-B},
researchr = {https://researchr.org/publication/LoyallK92},
cites = {0},
citedby = {0},
journal = {Journal of Computer Languages},
volume = {3},
number = {2},
pages = {107-133},
}