readme edits

README.md

@@ -6,9 +6,10 @@ U.S. Geological Survey (USGS) hazard software [*nshmp-haz*][1].
 For details on the format of this model, see the *nshmp-haz*
 [user guide and implementation reference][2].
 
-For prior models, see the [USGS Seismic Hazard Maps][3] web page.
+## Model Editions
 
-DOI: <https://doi.org/10.5066/P9J1OVR6> (version [5.1.0][4])
+* For prior models, see the [USGS Seismic Hazard Maps][3] web page.
+* Current edition: 2018, version [5.1.0][4].
 
 ## Site Files
 
@@ -17,13 +18,17 @@ maps of seismic hazard from this model. The `sites-conus.geojson` and `sites-con
 contain the test sites at which the USGS performs more detailed comparisons between model editions.
 See the *nshmp-haz* user guide [site specification section][5] for more details on these files.
 
-## Reference
+## References
 
-Petersen, M.D, Shumway, A.M., Powers, P.M., Mueller, C.S., Moschetti, M.P., Frankel, A.D.,
-Rezaeian, S., McNamara, D.E., Luco, N., Boyd, O.S., Rukstales, K.S., Jaiswal, K.S., Thompson, E.M.,
-Hoover, S.M., Clayton, B.S., Field, E.H., and Zeng, Y., 2020, The 2018 update of the U.S. National
-Seismic Hazard Model: Overview of model and implications, _Earthquake Spectra_, 36(1) p. 5–41,
-DOI: [10.1177/8755293019878199][6].
+**Model documentation:**  Petersen, M.D, Shumway, A.M., Powers, P.M., Mueller, C.S., Moschetti,
+M.P., Frankel, A.D., Rezaeian, S., McNamara, D.E., Luco, N., Boyd, O.S., Rukstales, K.S., Jaiswal,
+K.S., Thompson, E.M., Hoover, S.M., Clayton, B.S., Field, E.H., and Zeng, Y., 2020, The 2018
+update of the U.S. National Seismic Hazard Model: Overview of model and implications, _Earthquake
+Spectra_, 36(1) p. 5–41, doi: [10.1177/8755293019878199][6].
+
+**Suggested citation:**  Powers, P.M. and Altekruse, J.M., 2022, nshm-conus: National Seismic
+Hazard Model for the conterminous U.S. U.S. Geological Survey software release, doi:
+[10.5066/P9J1OVR6][7].
 
 [1]: https://code.usgs.gov/ghsc/nshmp/nshmp-haz
 [2]: https://code.usgs.gov/ghsc/nshmp/nshmp-haz/-/blob/main/docs/README.md
@@ -31,3 +36,4 @@ DOI: [10.1177/8755293019878199][6].
 [4]: https://code.usgs.gov/ghsc/nshmp/nshms/nshm-conus/-/tags/5.1.0
 [5]: https://code.usgs.gov/ghsc/nshmp/nshmp-haz/-/blob/main/docs/pages/Site-Specification.md
 [6]: https://doi.org/10.1177/8755293019878199
+[7]: https://doi.org/10.5066/P9J1OVR6