Symmetric closed categories

README.md

@@ -37,7 +37,11 @@ A curated list of awesome Category Theory resources.
 
   * [On the concreteness of certain categories](https://github.com/CategoryTheoryArchive/archive/blob/main/resources/1969_freyd_concreteness-certain.pdf) - This work discusses the concept of concreteness in categories, stating that a concrete category is one with a faithful functor to the category of sets, and must be locally-small. He highlights the homotopy category of spaces as a prime example of a non-concrete category, emphasizing its abstract nature due to the irrelevance of individual points within spaces and the inability to distinguish non-homotopic maps through any functor into concrete categories. Peter Freyd (1969)
 
-  * [V-localizations and V-triples](https://github.com/CategoryTheoryArchive/archive/blob/main/resources/1970_wolff_v-localizations-v-triples.pdf) This work focuses on two primary objectives within category theory. The first goal is to define and study Y-localizations of Y-categories, using a model akin to localizations in ordinary categories, involving certain conditions related to isomorphisms and the existence of unique Y-functors. The second aim is to explore the relationship between Y-localizations and V-triples, presenting foundational theories and examples to elucidate these concepts. Harvey Eli Wolff's dissertation (1970)
+  * [V-localizations and V-triples](https://github.com/CategoryTheoryArchive/archive/blob/main/resources/1970_wolff_v-localizations-v-triples.pdf) - This work focuses on two primary objectives within category theory. The first goal is to define and study Y-localizations of Y-categories, using a model akin to localizations in ordinary categories, involving certain conditions related to isomorphisms and the existence of unique Y-functors. The second aim is to explore the relationship between Y-localizations and V-triples, presenting foundational theories and examples to elucidate these concepts. Harvey Eli Wolff's dissertation (1970)
+
+  * [Symmetric closed categories](https://github.com/CategoryTheoryArchive/archive/blob/main/resources/1975_schipper_symmetric-closed.pdf) - This work is an in-depth exploration of category theory, focusing on closed categories, monoidal categories, and their symmetric counterparts. It discusses foundational concepts like natural transformations, tensor products, and the structure of morphisms, emphasizing their additional algebraic or topological structures. W. J. de Schipper (1975)
+
+  * [Algebraic theories](https://github.com/CategoryTheoryArchive/archive/blob/main/resources/1975_wraith_algebraic-theories.pdf) -
 
 ## Articles