diff --git a/DESCRIPTION b/DESCRIPTION
index cd1235662a7dd13d32edf55af92f63caa73dc00c..372bd31a214202c7fe132687edf2325192f03343 100644
--- a/DESCRIPTION
+++ b/DESCRIPTION
@@ -1,7 +1,7 @@
 Package: airGR
 Type: Package
 Title: Suite of GR Hydrological Models for Precipitation-Runoff Modelling
-Version: 1.0.12.0
+Version: 1.0.12.1
 Date: 2018-08-28
 Authors@R: c(
   person("Laurent", "Coron", role = c("aut", "trl"), comment = c(ORCID = "0000-0002-1503-6204")),
diff --git a/R/PEdaily_Oudin.R b/R/PEdaily_Oudin.R
index a896a0f79d1783078dc0bb66ee5670063ee7409a..4105fe9ab9067cdfecad31caf337cdb45f5792ed 100644
--- a/R/PEdaily_Oudin.R
+++ b/R/PEdaily_Oudin.R
@@ -7,6 +7,10 @@ PEdaily_Oudin <- function(JD, Temp, LatRad, Lat, LatUnit = c("rad", "deg")) {
     }
   }
   
+  if (!any(LatUnit %in%c("rad", "deg"))) {
+    stop("\"LatUnit\" must be \"rad\" or \"deg\".")
+  }
+  
   PE_Oudin_D <- rep(NA, length(Temp))
   
   if (LatUnit[1L] == "rad") {