diff --git a/13.0/apache/entrypoint.sh b/13.0/apache/entrypoint.sh
index 8e70509c..f3deaeeb 100755
--- a/13.0/apache/entrypoint.sh
+++ b/13.0/apache/entrypoint.sh
@@ -131,7 +131,7 @@ fi
 
 ## APACHE SSL configuration (self signed certificates)
 ## ENV VAR set dan dit uitvoeren nog inbouwen
-if expr "$1" : "apache" 1 || [-n "${APACHE_SSL_SELFSIGNED+x}" "true" ]; then
+if expr "$1" : "apache" 1 || [ "${APACHE_SSL_SELFSIGNED+x}" "true" ]; then
   a2enmod ssl
   a2enmod headers
   openssl genrsa -out ca.key 2048
diff --git a/13.0/fpm-alpine/entrypoint.sh b/13.0/fpm-alpine/entrypoint.sh
index 8e70509c..f3deaeeb 100755
--- a/13.0/fpm-alpine/entrypoint.sh
+++ b/13.0/fpm-alpine/entrypoint.sh
@@ -131,7 +131,7 @@ fi
 
 ## APACHE SSL configuration (self signed certificates)
 ## ENV VAR set dan dit uitvoeren nog inbouwen
-if expr "$1" : "apache" 1 || [-n "${APACHE_SSL_SELFSIGNED+x}" "true" ]; then
+if expr "$1" : "apache" 1 || [ "${APACHE_SSL_SELFSIGNED+x}" "true" ]; then
   a2enmod ssl
   a2enmod headers
   openssl genrsa -out ca.key 2048
diff --git a/13.0/fpm/entrypoint.sh b/13.0/fpm/entrypoint.sh
index 8e70509c..f3deaeeb 100755
--- a/13.0/fpm/entrypoint.sh
+++ b/13.0/fpm/entrypoint.sh
@@ -131,7 +131,7 @@ fi
 
 ## APACHE SSL configuration (self signed certificates)
 ## ENV VAR set dan dit uitvoeren nog inbouwen
-if expr "$1" : "apache" 1 || [-n "${APACHE_SSL_SELFSIGNED+x}" "true" ]; then
+if expr "$1" : "apache" 1 || [ "${APACHE_SSL_SELFSIGNED+x}" "true" ]; then
   a2enmod ssl
   a2enmod headers
   openssl genrsa -out ca.key 2048
diff --git a/14.0/apache/entrypoint.sh b/14.0/apache/entrypoint.sh
index 8e70509c..f3deaeeb 100755
--- a/14.0/apache/entrypoint.sh
+++ b/14.0/apache/entrypoint.sh
@@ -131,7 +131,7 @@ fi
 
 ## APACHE SSL configuration (self signed certificates)
 ## ENV VAR set dan dit uitvoeren nog inbouwen
-if expr "$1" : "apache" 1 || [-n "${APACHE_SSL_SELFSIGNED+x}" "true" ]; then
+if expr "$1" : "apache" 1 || [ "${APACHE_SSL_SELFSIGNED+x}" "true" ]; then
   a2enmod ssl
   a2enmod headers
   openssl genrsa -out ca.key 2048
diff --git a/14.0/fpm-alpine/entrypoint.sh b/14.0/fpm-alpine/entrypoint.sh
index 8e70509c..f3deaeeb 100755
--- a/14.0/fpm-alpine/entrypoint.sh
+++ b/14.0/fpm-alpine/entrypoint.sh
@@ -131,7 +131,7 @@ fi
 
 ## APACHE SSL configuration (self signed certificates)
 ## ENV VAR set dan dit uitvoeren nog inbouwen
-if expr "$1" : "apache" 1 || [-n "${APACHE_SSL_SELFSIGNED+x}" "true" ]; then
+if expr "$1" : "apache" 1 || [ "${APACHE_SSL_SELFSIGNED+x}" "true" ]; then
   a2enmod ssl
   a2enmod headers
   openssl genrsa -out ca.key 2048
diff --git a/14.0/fpm/entrypoint.sh b/14.0/fpm/entrypoint.sh
index 8e70509c..f3deaeeb 100755
--- a/14.0/fpm/entrypoint.sh
+++ b/14.0/fpm/entrypoint.sh
@@ -131,7 +131,7 @@ fi
 
 ## APACHE SSL configuration (self signed certificates)
 ## ENV VAR set dan dit uitvoeren nog inbouwen
-if expr "$1" : "apache" 1 || [-n "${APACHE_SSL_SELFSIGNED+x}" "true" ]; then
+if expr "$1" : "apache" 1 || [ "${APACHE_SSL_SELFSIGNED+x}" "true" ]; then
   a2enmod ssl
   a2enmod headers
   openssl genrsa -out ca.key 2048
diff --git a/15.0/apache/entrypoint.sh b/15.0/apache/entrypoint.sh
index 8e70509c..f3deaeeb 100755
--- a/15.0/apache/entrypoint.sh
+++ b/15.0/apache/entrypoint.sh
@@ -131,7 +131,7 @@ fi
 
 ## APACHE SSL configuration (self signed certificates)
 ## ENV VAR set dan dit uitvoeren nog inbouwen
-if expr "$1" : "apache" 1 || [-n "${APACHE_SSL_SELFSIGNED+x}" "true" ]; then
+if expr "$1" : "apache" 1 || [ "${APACHE_SSL_SELFSIGNED+x}" "true" ]; then
   a2enmod ssl
   a2enmod headers
   openssl genrsa -out ca.key 2048
diff --git a/15.0/fpm-alpine/entrypoint.sh b/15.0/fpm-alpine/entrypoint.sh
index 8e70509c..f3deaeeb 100755
--- a/15.0/fpm-alpine/entrypoint.sh
+++ b/15.0/fpm-alpine/entrypoint.sh
@@ -131,7 +131,7 @@ fi
 
 ## APACHE SSL configuration (self signed certificates)
 ## ENV VAR set dan dit uitvoeren nog inbouwen
-if expr "$1" : "apache" 1 || [-n "${APACHE_SSL_SELFSIGNED+x}" "true" ]; then
+if expr "$1" : "apache" 1 || [ "${APACHE_SSL_SELFSIGNED+x}" "true" ]; then
   a2enmod ssl
   a2enmod headers
   openssl genrsa -out ca.key 2048
diff --git a/15.0/fpm/entrypoint.sh b/15.0/fpm/entrypoint.sh
index 8e70509c..f3deaeeb 100755
--- a/15.0/fpm/entrypoint.sh
+++ b/15.0/fpm/entrypoint.sh
@@ -131,7 +131,7 @@ fi
 
 ## APACHE SSL configuration (self signed certificates)
 ## ENV VAR set dan dit uitvoeren nog inbouwen
-if expr "$1" : "apache" 1 || [-n "${APACHE_SSL_SELFSIGNED+x}" "true" ]; then
+if expr "$1" : "apache" 1 || [ "${APACHE_SSL_SELFSIGNED+x}" "true" ]; then
   a2enmod ssl
   a2enmod headers
   openssl genrsa -out ca.key 2048
diff --git a/docker-entrypoint.sh b/docker-entrypoint.sh
index 8e70509c..f3deaeeb 100755
--- a/docker-entrypoint.sh
+++ b/docker-entrypoint.sh
@@ -131,7 +131,7 @@ fi
 
 ## APACHE SSL configuration (self signed certificates)
 ## ENV VAR set dan dit uitvoeren nog inbouwen
-if expr "$1" : "apache" 1 || [-n "${APACHE_SSL_SELFSIGNED+x}" "true" ]; then
+if expr "$1" : "apache" 1 || [ "${APACHE_SSL_SELFSIGNED+x}" "true" ]; then
   a2enmod ssl
   a2enmod headers
   openssl genrsa -out ca.key 2048