Node:Reference Syntax, Next:One Argument, Previous:xref, Up:xref
Most often, an Info cross reference looks like this:
*Note node-name::.
or like this
*Note cross-reference-name: node-name.
In TeX, a cross reference looks like this:
See Section section-number [node-name], page page.
or like this
See Section section-number [title-or-topic], page page.
The @xref command does not generate a period or comma to end
the cross reference in either the Info file or the printed output. 
You must write that period or comma yourself; otherwise, Info will not
recognize the end of the reference.  (The @pxref command works
differently.  See @pxref.)
Please note: A period or comma must follow the closing
brace of an @xref.  It is required to terminate the cross
reference.  This period or comma will appear in the output, both in
the Info file and in the printed manual. 
@xref must refer to an Info node by name.  Use @node
to define the node (see Writing a Node).
@xref is followed by several arguments inside braces, separated by
commas.  Whitespace before and after these commas is ignored.
A cross reference requires only the name of a node; but it may contain up to four additional arguments. Each of these variations produces a cross reference that looks somewhat different.
Please note: Commas separate arguments in a cross reference; avoid including them in the title or other part lest the formatters mistake them for separators.