To help you with the citations: Garbage collectors: "Recursive Functions of Symbolic Expressions and Their Computation by Machine, Part I", John McCarthy, Comm

To help you with the citations: Garbage collectors: "Recursive Functions of Symbolic Expressions and Their Computation by Machine, Part I", John McCarthy, Communications of the ACM, 1960-04, pp. 184-195 (open access at ACM). Stacks and stack pointers: "Recursive Programming", Edsger Wybe Dijkstra, 1960-05-11 (available at the Dijkstra Archive). Reference counts for memory allocation: "A Method for Overlapping and Erasure of Lists", George E. Collins (IBM), Communications of the ACM, Volume 3, Issue 12, 1960-12, pp. 655–657 (open access at ACM). The first "malloc", i.e. the statements "ALLOCATE" and "FREE" appeared in "NPL Technical Report" at IBM in 1964-12 (available at bitsavers.org). "NPL" was a provisional name for the new programming language of IBM, which was rebranded as "PL/I" when it was launched officially, a half of year later. IBM did not document what kind of algorithm was used by their "malloc" implementation, but it already had to handle multi-threaded programs and it was specified that when a new thread was spawned, it could still access any variable that had been dynamically allocated in the parent thread, before the launching of the new thread, but the variables that were allocated in the new thread were private to that thread. The C "malloc" became compatible with multi-threading only many decades after its ancestor from PL/I.