diff --git a/Project.toml b/Project.toml
index b8d8c4c..de21227 100644
--- a/Project.toml
+++ b/Project.toml
@@ -18,7 +18,7 @@ Unitful = "1986cc42-f94f-5a68-af5c-568840ba703d"
 ConstructionBase = "1.0"
 EquationsOfState = "4.0"
 Functors = "0.3, 0.4"
-LsqFit = "0.8, 0.9, 0.10, 0.11, 0.12, 0.13"
+LsqFit = "0.8, 0.9, 0.10, 0.11, 0.12, 0.13, 0.15"
 PolynomialRoots = "1.0"
 Polynomials = "0.8, 1.0, 2.0, 3, 4"
 Roots = "0.8, 1.0, 2"