If it is cited as a TR, it is a TR.
One can imagine adding a cross-reference field to references that points to associated documents or other references.
An official report on a bout of graduate work for which one receives a degree, published by the university. Never mind that some fields make a big deal about the difference between dissertations and theses. From the bibliographic perspective, they are both of the same family.
(=> (Thesis ?X) (And (Value-Cardinality ?X Has-Author 1) (Value-Cardinality ?X Title-Of 1) (Value-Cardinality ?X Publication-Date-Of 1) (Value-Cardinality ?X Organization-Of 1) (Value-Type ?X Organization-Of University)))
(Subclass-Partition Document (Setof Book Periodical-Publication Proceedings Thesis Technical-Report Miscellaneous-Publication))