Here is one such paper,
https://www.lri.fr/~mbl/ENS/FundHCI/2013/papers/XeroxStar-Co...
A few quotes from it,
> SunView is an example of a window system that is based upon the Tools metaphor rather than the Desktop metaphor. Its users see a collection of application program windows, each of which is used to edit certain files. Smalltalk-80, Cedar, and various Lisp environments also use the Tools metaphor rather than the Desktop metaphor
> The Reactive Engine -- While Engelbart et al were developing ideas, some of which eventually found their way into Star, Alan Kay, then a graduate student, was doing likewise. His dissertation, The Reactive Engine, contained seeds of many ideas that he and others later brought to fruition in the Smalltalk language and programming environment, which, in turn, influenced Star.
> Most importantly for Star, they demonstrated the power of graphical,
bitmapped displays, mouse-driven input, windows, and simultaneous applications. This is the most visible link between Smalltalk and Star, and is perhaps why many people wrongly believe that Star was written in Smalltalk.
> Even though the machine was designed to run Star, it also ran other software. In addition to selling it as the 8010 "Star" workstation, Xerox sold it as a server machine and as an Interlisp and a Smalltalk workstation.
From this other one, some quotes as well,
"The Mesa Programming Environment"
https://dl.acm.org/doi/pdf/10.1145/17919.806843
> Client programs can attach additional information to windows by means of named contexts, similar to property lists of LISP. Tools can be written to have multiple instances, obtaining their data from the context associated with the particular window that Tajo is notifying (passed as a parameter to the notify procedure).
> The debugger had multiple windows patterned after those of Smalltalk [Kay76]. One, a typescript window, was used for interaction with the debugger executive for setting breakpoints, examining data, etc., and another was used to show the source context at breakpoints.
There are a few others with similar one off sentences like these, telling how designers from one system got influenced by the other, while at Xerox PARC.