Returns the names of all workbooks referred to by external references in the workbook specified
[C++]
static int Links(
   std::vector<CString>& links,
   const char* document_text = "",
   short int type_num = 1
);
A vector of strings which will be populated with the list of names.
Document_text is the name of a workbook, including its path.
Type_num is a number from 1 to 6 specifying the type of linked workbooks to return.
Zero if the function has been called successfully; non-zero
            if the function could not be called.
            See Error codes for a list
            of return values.
See the Microsoft Excel on-line Help for full details about
            this function.
Header: xlfuncs.h