In the following paragraph, should there be an apostrophe associated with systems. I interpret systems to refer to the previously listed sytems and therfore should be systems'. An argument could be made that there is a system composed of the elements listed and therefore systems should be system's. An argument could also be made that systems modifies resources so no apostrophe is needed. If anyone could cite a rule or offer comments I would be very grateful. Thanks.
Vjk
"This Network Requirements Document (NRD) defines the service requirements between the
Orbiting Carbon Observatory-2 (OCO-2) Spacecraft (S/C), the Space Network

, NASA
Integrated Services Network (NISN), Flight Dynamics Facility (FDF), Earth Observing System
(EOS) Data and Operations System (EDOS), and the Near Earth Network (NEN) systems
resources."