fix reference entry

how_to_eurec4a/references.bib

@@ -207,10 +207,10 @@ @article{Held:2019
   title = {Structure and {{Performance}} of {{GFDL}}'s {{CM4}}.0 {{Climate Model}}},
   author = {Held, I. M. and Guo, H. and Adcroft, A. and Dunne, J. P. and Horowitz, L. W. and Krasting, J. and Shevliakova, E. and Winton, M. and Zhao, M. and Bushuk, M. and Wittenberg, A. T. and Wyman, B. and Xiang, B. and Zhang, R. and Anderson, W. and Balaji, V. and Donner, L. and Dunne, K. and Durachta, J. and Gauthier, P. P. G. and Ginoux, P. and Golaz, J.-C. and Griffies, S. M. and Hallberg, R. and Harris, L. and Harrison, M. and Hurlin, W. and John, J. and Lin, P. and Lin, S.-J. and Malyshev, S. and Menzel, R. and Milly, P. C. D. and Ming, Y. and Naik, V. and Paynter, D. and Paulot, F. and Ramaswamy, V. and Reichl, B. and Robinson, T. and Rosati, A. and Seman, C. and Silvers, L. G. and Underwood, S. and Zadeh, N.},
   year = {2019},
-  journaltitle = {Journal of Advances in Modeling Earth Systems},
+  journal = {Journal of Advances in Modeling Earth Systems},
   volume = {11},
   number = {11},
   pages = {3691--3727},
   issn = {1942-2466},
   doi = {10.1029/2019MS001829},
-}
+}