diff --git a/Project.toml b/Project.toml
index b07b7b79..209a596c 100644
--- a/Project.toml
+++ b/Project.toml
@@ -66,6 +66,7 @@ RuntimeGeneratedFunctions = "0.4, 0.5"
 SBML = "1"
 SciMLBase = "1"
 SciMLSensitivity = "6 - 7"
+SpecialFunctions = "2"
 StatsBase = "0.33, 0.34"
 SteadyStateDiffEq = "1"
 Sundials = "4"