diff --git a/Project.toml b/Project.toml
index 7022e906c..37e51be60 100644
--- a/Project.toml
+++ b/Project.toml
@@ -26,7 +26,7 @@ ADNLPModels = "0.8"
 BenchmarkTools = "1"
 CTBase = "0.30"
 CTDirect = "1"
-CTFlows = "0.18"
+CTFlows = "0.18, 0.17"
 CTLie = "0.2"
 CTModels = "0.19"
 CTParser = "0.9"