VMS Help DSR, DSR Commands, .REQUIRE, Parameter  *Conan The Librarian (sorry for the slow response - running on an old VAX)

 filespec

    A file specification enclosed in quotation marks or apostrophes.
    If you just specify a file name, the default file type is .RNO.
    If you do not supply a full file specification, DSR uses your
    default device and directory. If you want to include (.REQUIRE)
    files from other devices or directories, you must specify the
    full file specification.