Info-read-node-name is a compiled Lisp function in `info.el'.

(Info-read-node-name PROMPT)

Read an Info node name with completion, prompting with PROMPT.
A node name can have the form "NODENAME", referring to a node
in the current Info file, or "(FILENAME)NODENAME", referring to
a node in FILENAME. "(FILENAME)" is a short format to go to
the Top node in FILENAME.