One particular area of Al’s work was not only interdisciplinary, it was trans-disciplinary.
Al was one of the earliest workers to appreciate and contribute to the systems awareness movement, although he favored the systems science strain over the systems thinking strain. He had a vital interest in hierarchy as an isomorphic systems pattern and organizing one of the first conferences on an isomorphy (hierarchy; see first reference here). But he also had an interest in several other isomorphies as demonstrated below.
He also was very interested in the contributions that linguistic patterns could make to the search for isomorphs.
Along with the Isomophies below, one can use the search function in this website to find references to other isomorphies such as Boundary, Networks, and Feedback in Al’s notebooks.