diff --git a/INSTALL.md b/INSTALL.md
index fc12576..9140d3f 100644
--- a/INSTALL.md
+++ b/INSTALL.md
@@ -1,7 +1,7 @@
 # Generic installation
 
 ```bash
-opam install ocamlbuild lacaml mpi getopt alcotest zarith
+opam install ocamlbuild ocamlfind lacaml mpi getopt alcotest zarith
 ```
 
 
diff --git a/Simulation.ml b/Simulation.ml
index c8287bd..2a1726f 100644
--- a/Simulation.ml
+++ b/Simulation.ml
@@ -35,15 +35,15 @@ let make ?cartesian:(cartesian=false)
     Electrons.make ~multiplicity ~charge nuclei
   in
 
-  let chargre = 
+  let charge = 
     Charge.(Nuclei.charge nuclei + Electrons.charge electrons)
   in
 
-  let ao_basis = 
+  let ao_basis =
     AOBasis.make ?f12 ~basis ~cartesian nuclei
   in
 
-  let nuclear_repulsion = 
+  let nuclear_repulsion =
     Nuclei.repulsion nuclei
   in