add reference to citation guidelines

how_to_eurec4a/howto_cite_dataset.md

@@ -3,4 +3,6 @@
 This How-To book is based on two main components, the EUREC$^4$A Intake catalog and the datasets referenced therein.
 
 The EUREC$^4$ Intake catalog is published at [![](https://zenodo.org/badge/doi/10.5281/zenodo.8422321.svg)](https://doi.org/10.5281/zenodo.8422321) and can be cited accordingly.
-Please note however that this is a collection DOI and will always point to the most recent published version of the catalog. 
+Please note however that this is a collection DOI and will always point to the most recent published version of the catalog. To give credit to the authors of the individual datasets, the used datasets should be cited in addition to the EUREC$^4$A Intake catalog.
+
+Further information and citation examples can be found in the [EUREC$^4$ Intake catalog citation guidelines](https://github.com/eurec4a/eurec4a-intake/blob/master/CITATION.md).