diff --git a/auxiliary_packages/funman_benchmarks/src/funman_benchmarks/_version.py b/auxiliary_packages/funman_benchmarks/src/funman_benchmarks/_version.py
index 3bca77a1..6adb2512 100644
--- a/auxiliary_packages/funman_benchmarks/src/funman_benchmarks/_version.py
+++ b/auxiliary_packages/funman_benchmarks/src/funman_benchmarks/_version.py
@@ -1,4 +1,4 @@
 """Version information."""
 
 # The following line *must* be the last in the module, exactly as formatted:
-__version__ = "1.9.0"
+__version__ = "1.9.1"
diff --git a/auxiliary_packages/funman_demo/src/funman_demo/_version.py b/auxiliary_packages/funman_demo/src/funman_demo/_version.py
index 3bca77a1..6adb2512 100644
--- a/auxiliary_packages/funman_demo/src/funman_demo/_version.py
+++ b/auxiliary_packages/funman_demo/src/funman_demo/_version.py
@@ -1,4 +1,4 @@
 """Version information."""
 
 # The following line *must* be the last in the module, exactly as formatted:
-__version__ = "1.9.0"
+__version__ = "1.9.1"
diff --git a/auxiliary_packages/funman_dreal/src/funman_dreal/_version.py b/auxiliary_packages/funman_dreal/src/funman_dreal/_version.py
index 3bca77a1..6adb2512 100644
--- a/auxiliary_packages/funman_dreal/src/funman_dreal/_version.py
+++ b/auxiliary_packages/funman_dreal/src/funman_dreal/_version.py
@@ -1,4 +1,4 @@
 """Version information."""
 
 # The following line *must* be the last in the module, exactly as formatted:
-__version__ = "1.9.0"
+__version__ = "1.9.1"
diff --git a/auxiliary_packages/pde2petri/src/pde2petri/_version.py b/auxiliary_packages/pde2petri/src/pde2petri/_version.py
index 0a0a43a5..38cf6dbe 100644
--- a/auxiliary_packages/pde2petri/src/pde2petri/_version.py
+++ b/auxiliary_packages/pde2petri/src/pde2petri/_version.py
@@ -1 +1 @@
-__version__ = "1.9.0"
+__version__ = "1.9.1"
diff --git a/docker/dreal4/Dockerfile.dreal4 b/docker/dreal4/Dockerfile.dreal4
index ea6dbce1..7be71dcb 100644
--- a/docker/dreal4/Dockerfile.dreal4
+++ b/docker/dreal4/Dockerfile.dreal4
@@ -71,10 +71,11 @@ RUN cd /dreal4 \
       && bazel build //:archive \
       && tar xfz bazel-bin/archive.tar.gz --strip-components 3 -C /usr \
 # Install Python3 Binding
-      && pip3 install wheel \
+      && pip3 install --upgrade wheel \
+      && pip3 install --upgrade setuptools \
       && pip3 install --upgrade pip \
       && python3 setup.py bdist_wheel \
-      && DREAL_WHEEL=dreal-*-cp38-none-manylinux_$(ldd --version | grep '^ldd' | sed -E 's/^ldd.*([0-9]+)\.([0-9]+)$/\1_\2/')_$(arch).whl \
+      && DREAL_WHEEL=dreal-$(python setup.py --version)-cp38-none-manylinux_$(ldd --version | grep '^ldd' | sed -E 's/^ldd.*([0-9]+)\.([0-9]+)$/\1_\2/')_$(arch).whl \
       && cp ./dist/$DREAL_WHEEL /tmp/$DREAL_WHEEL \
       && pip3 install ./dist/$DREAL_WHEEL \
       && bazel clean --expunge \
diff --git a/src/funman/_version.py b/src/funman/_version.py
index 3bca77a1..6adb2512 100644
--- a/src/funman/_version.py
+++ b/src/funman/_version.py
@@ -1,4 +1,4 @@
 """Version information."""
 
 # The following line *must* be the last in the module, exactly as formatted:
-__version__ = "1.9.0"
+__version__ = "1.9.1"