See the NDACC website for the full NDACC Data Use Agreement. All NDACC data users at a minimum should acknowledge both the NDACC DHF and the NDACC PI in any publication, as follows: "The data used in this publication were obtained from "NDACC PI name" as part of the Network for the Detection of Atmospheric Composition Change (NDACC) and are available through NDACC website."