This is the official manual for the latest Org-mode release.
Language-specific header arguments are also read from properties
<lang> is the name of the language
targeted. As an example
* Heading :PROPERTIES: :header-args:clojure: :session *clojure-1* :header-args:R: :session *R* :END: ** Subheading :PROPERTIES: :header-args:clojure: :session *clojure-2* :END:
would independently set a default session header argument for R and clojure for calls and source blocks under subtree “Heading” and change to a different clojure setting for evaluations under subtree “Subheading”, while the R session is inherited from “Heading” and therefore unchanged.