add references in documentation

README.md

@@ -144,4 +144,17 @@ power_function_args = dict()
 ```
 
 ### References
-- NORA3 dataset 
+
+Science
+- H Hersbach et al., "The ERA5 global Reanalysis", https://doi.org/10.1002/qj.3803
+- H Haakenstad et al., "NORA3: A Nonhydrostatic High-Resolution Hindcast of the North Sea, the Norwegian Sea, and the Barents Sea", 
+https://doi.org/10.1175/JAMC-D-21-0029.1
+- IM Solbrekke, A Sorteberg, H Haakenstad, "The 3 km Norwegian reanalysis (NORA3) – a validation of offshore wind resources in the North Sea and the Norwegian Sea", https://doi.org/10.5194/wes-6-1501-2021
+- I Stafell, S Pfenninger, "Using bias-corrected reanalysis to simulate current and future wind power output", https://doi.org/10.1016/j.energy.2016.08.068, https://www.renewables.ninja/documentation/science
+
+Data and APIs
+- metocean-api documentation: https://metocean-api.readthedocs.io/en/latest/index.html
+- ECMWF Reanalysis v5 ERA5, https://www.ecmwf.int/en/forecasts/dataset/ecmwf-reanalysis-v5
+- WindPRO NORA3 page, https://help.emd.dk/mediawiki/index.php/NORA3 
+- WindPRO ERA5 page, https://help.emd.dk/mediawiki/index.php/ERA5_Gaussian_Grid
+