diff --git a/vignettes/V02.1_param_optim.Rmd b/vignettes/V02.1_param_optim.Rmd
index 1b0589766153f986c53cb5a351ea5d66f64de9ac..7e1b7aed96b622e49513a339a1ad87c5e091a48c 100644
--- a/vignettes/V02.1_param_optim.Rmd
+++ b/vignettes/V02.1_param_optim.Rmd
@@ -162,11 +162,12 @@ optDE <- DEoptim::DEoptim(fn = OptimGR4J,
 
 
 ## Particle Swarm
+
 ```{r, warning=FALSE, results='hide', message=FALSE, eval=FALSE}
-# to install the package temporary removde from CRAN
+# to install the package temporary removed from CRAN
 # Rtools needed (windows : https://cran.r-project.org/bin/windows/Rtools/)
-install.packages("https://cran.r-project.org/src/contrib/Archive/hydroPSO/hydroPSO_0.5-1.tar.gz", 
-                 repos = NULL, type = "source", dependencies = TRUE)
+# install.packages("https://cran.r-project.org/src/contrib/Archive/hydroPSO/hydroPSO_0.5-1.tar.gz", 
+#                  repos = NULL, type = "source", dependencies = TRUE)
 ```