diff --git a/Project.toml b/Project.toml
index 48980c5..af796b0 100644
--- a/Project.toml
+++ b/Project.toml
@@ -22,7 +22,7 @@ Statistics = "10745b16-79ce-11e8-11f9-7d13ad32a3b2"
 BlackBoxOptim = "0.6"
 Colors = "0.12"
 HDF5 = "0.16"
-Interpolations = "0.13"
+Interpolations = "0.13, 0.15"
 LaTeXStrings = "1"
 Optim = "1"
 Polynomials = "3"