diff --git a/Project.toml b/Project.toml
index cc7f22f1..2afaa4c5 100644
--- a/Project.toml
+++ b/Project.toml
@@ -51,6 +51,7 @@ ApproxManifoldProducts = "0.8"
 CoordinateTransformations = "0.5, 0.6"
 Dates = "1.10"
 DelimitedFiles = "1"
+DifferentialEquations = "7"
 Distributed = "1.10"
 DistributedFactorGraphs = "0.23"
 Distributions = "0.24, 0.25"