diff --git a/doc/walberla.bib b/doc/walberla.bib
index 8fbf7ae689fdd6b16bff958aaeabaf2427f18600..9dc2a2a88171c1bf2b94cf4eea25e43364968b08 100644
--- a/doc/walberla.bib
+++ b/doc/walberla.bib
@@ -9,6 +9,7 @@
   volume    = {31},
   number    = {6},
   pages     = {529--542},
+  url       = {https://dx.doi.org/10.1080/17445760.2015.1118478},
   doi       = {10.1080/17445760.2015.1118478},
 }
 
@@ -20,6 +21,7 @@
   pages        = {35},
   organization = {ACM},
   publisher    = {Association for Computing Machinery},
+  url          = {https://dx.doi.org/10.1145/2503210.2503273},
   doi          = {10.1145/2503210.2503273},
   isbn         = {9781450323789},
 }
@@ -32,6 +34,7 @@
   volume  = {38},
   number  = {2},
   pages   = {C96-C126},
+  url     = {https://dx.doi.org/10.1137/15M1035240},
   doi     = {10.1137/15M1035240},
 }
 
@@ -43,6 +46,7 @@
   volume    = {16},
   number    = {1},
   pages     = {607--608},
+  url       = {https://dx.doi.org/10.1002/pamm.201610292},
   doi       = {10.1002/pamm.201610292},
   publisher = {Wiley Online Library},
 }
@@ -54,6 +58,7 @@
   volume    = {154},
   pages     = {74--89},
   year      = {2017},
+  url       = {https://dx.doi.org/10.1016/j.compfluid.2017.05.033},
   doi       = {10.1016/j.compfluid.2017.05.033}
 }
 
@@ -65,6 +70,7 @@
   year      = {2017},
   publisher = {Springer International Publishing},
   pages     = {3--21},
+  url       = {https://dx.doi.org/10.1007/978-3-319-58667-0_1},
   doi       = {10.1007/978-3-319-58667-0_1}
 }
 
@@ -74,6 +80,7 @@
   volume    = {172},
   pages     = {706--719},
   year      = {2018},
+  url       = {https://dx.doi.org/10.1016/j.compfluid.2018.01.023},
   doi       = {10.1016/j.compfluid.2018.01.023},
   author    = {Rettinger, Christoph and R{\"u}de, Ulrich}
 }
@@ -85,6 +92,7 @@
   volume    = {7},
   number    = {1},
   year      = {2019},
+  url       = {https://dx.doi.org/10.3390/computation7010009},
   doi       = {10.3390/computation7010009}
 }
 
@@ -108,6 +116,7 @@
   number    = {3},
   pages     = {511--525},
   publisher = {APS},
+  url       = {https://dx.doi.org/10.1103/PhysRev.94.511},
   doi       = {10.1103/PhysRev.94.511},
 }
 
@@ -120,6 +129,7 @@
   number    = {1792},
   pages     = {437--451},
   publisher = {The Royal Society},
+  url       = {https://dx.doi.org/10.1098/rsta.2001.0955},
   doi       = {10.1098/rsta.2001.0955},
 }
 
@@ -132,6 +142,7 @@
   number    = {8},
   pages     = {898--909},
   publisher = {Elsevier},
+  url       = {https://dx.doi.org/10.1016/j.compfluid.2005.03.008},
   doi       = {10.1016/j.compfluid.2005.03.008},
 }
 
@@ -144,6 +155,7 @@
   number    = {4},
   pages     = {507--547},
   publisher = {Elsevier},
+  url       = {https://dx.doi.org/10.1016/j.camwa.2015.05.001},
   doi       = {10.1016/j.camwa.2015.05.001},
 }
 
@@ -156,6 +168,7 @@
   number    = {4},
   pages     = {046308},
   publisher = {APS},
+  url       = {https://dx.doi.org/10.1103/PhysRevE.65.046308},
   doi       = {10.1103/PhysRevE.65.046308},
 }
 
@@ -176,6 +189,7 @@
   number    = {4},
   pages     = {2941--2948},
   publisher = {APS},
+  url       = {https://dx.doi.org/10.1103/PhysRevE.49.2941},
   doi       = {10.1103/PhysRevE.49.2941},
 }
 
@@ -184,6 +198,7 @@
   title     = {Thermal fluctuations and boundary conditions in the lattice {Boltzmann} method},
   school    = {Johannes Gutenberg-Universit{\"a}t, Mainz},
   year      = {2008},
+  url       = {https://dx.doi.org/10.25358/openscience-3231},
   doi       = {10.25358/openscience-3231},
 }
 
@@ -192,6 +207,7 @@
   title     = {Hydrodynamic limit of lattice {Boltzmann} equations},
   school    = {University of Geneva},
   year      = {2007},
+  url       = {https://dx.doi.org/10.13097/archive-ouverte/unige:464},
   doi       = {10.13097/archive-ouverte/unige:464},
 }
 
@@ -252,6 +268,7 @@
   author = {Ladd, Anthony JC},
   year = {1994},
   pages = {285--309},
+  url = {https://dx.doi.org/10.1017/S0022112094001771},
   doi = {10.1017/S0022112094001771}
 }
 
@@ -262,6 +279,7 @@
   author = {Aidun, Cyrus K. and Lu, Yannan and Ding, E.-Jiang},
   year = {1998},
   pages = {287--311},
+  url = {https://dx.doi.org/10.1017/S0022112098002493},
   doi = {10.1017/S0022112098002493}
 }
 
@@ -269,6 +287,7 @@
   title = {A Lattice-{Boltzmann} Method for Partially Saturated Computational Cells},
   volume = {09},
   issn = {0129-1831},
+  url = {https://dx.doi.org/10.1142/S0129183198001084},
   doi = {10.1142/S0129183198001084},
   number = {08},
   journal = {International Journal of Modern Physics C},
@@ -284,6 +303,7 @@
   pages = {105 - 127},
   year = {2017},
   issn = {0021-9991},
+  url = {https://dx.doi.org/10.1016/j.jcp.2017.03.035},
   doi = {10.1016/j.jcp.2017.03.035},
   author = {Edward Biegert and Bernhard Vowinckel and Eckart Meiburg}
 }
@@ -298,6 +318,7 @@
   numpages = {12},
   year = {2002},
   publisher = {American Physical Society},
+  url = {https://dx.doi.org/10.1103/PhysRevE.66.046708},
   doi = {10.1103/PhysRevE.66.046708}
 }
 
@@ -308,6 +329,7 @@
   pages = {36--48},
   year = {2018},
   issn = {0167-8191},
+  url = {https://dx.doi.org/10.1016/j.parco.2018.10.002},
   doi = {10.1016/j.parco.2018.10.002},
   author = {Eibl, Sebastian and R{\"u}de, Ulrich}
 }
@@ -319,6 +341,7 @@
   pages = {591--613},
   year = {2015},
   issn = {0021-9991},
+  url = {https://dx.doi.org/10.1016/j.jcp.2014.10.039},
   doi = {10.1016/j.jcp.2014.10.039},
   author = {S. Schwarz and T. Kempe and J. Fr{\"o}hlich},
 }
@@ -329,6 +352,7 @@
   booktitle = {Proceedings of the International Conference for High Performance Computing, Networking, Storage and Analysis},
   pages = {1--32},
   year = {2019},
+  url = {https://dx.doi.org/10.1145/3295500.3356186},
   doi = {10.1145/3295500.3356186}
 }
 
@@ -340,6 +364,7 @@
   publisher = {Elsevier},
   volume = {81},
   pages = {478-501},
+  url = {https://dx.doi.org/10.1016/j.camwa.2020.01.007},
   doi = {10.1016/j.camwa.2020.01.007}
 }
 
@@ -350,6 +375,7 @@
   volume = {49},
   pages = {101269},
   year = {2021},
+  url = {https://dx.doi.org/10.1016/j.jocs.2020.101269},
   doi = {10.1016/j.jocs.2020.101269},
 }