diff --git a/book.bib b/book.bib
index d8d5b35..2ccd37f 100644
--- a/book.bib
+++ b/book.bib
@@ -77,7 +77,7 @@ @article{Mina1986
   volume = {1},
   number = {2},
   pages = {53--56},
-  month = {Jun},
+  month = {6},
   year = {1986},
   publisher = {{SAGE} Publications},
   doi = {10.1177/088610998600100206}
@@ -89,7 +89,7 @@ @article{Mori2012
   publisher = {Public Library of Science ({PLoS})},
   title = {A Quick Guide to Software Licensing for the Scientist-Programmer},
   year = {2012},
-  month = {Jul},
+  month = {7},
   volume = {8},
   number = {7},
   link = {https://doi.org/10.1371/journal.pcbi.1002598},