Please cite both the package and the original articles / software in your publications:
Mouselimis L (2022). CopernicusDEM: Copernicus Digital Elevation Models. R package version 1.0.2 produced using Copernicus WorldDEMTM-90 DLR e.V. 2010-2014 and Airbus Defence and Space GmbH 2014-2018 provided under COPERNICUS by the European Union and ESA; all rights reserved, https://CRAN.R-project.org/package=CopernicusDEM.
Corresponding BibTeX entry:
@Manual{, title = {{CopernicusDEM}: Copernicus Digital Elevation Models}, author = {Lampros Mouselimis}, year = {2022}, note = {R package version 1.0.2 produced using Copernicus WorldDEMTM-90 DLR e.V. 2010-2014 and Airbus Defence and Space GmbH 2014-2018 provided under COPERNICUS by the European Union and ESA; all rights reserved}, url = {https://CRAN.R-project.org/package=CopernicusDEM}, }