diff --git a/easybuild/easyconfigs/c/ConcurrentVersionsSystem/ConcurrentVersionsSystem-1.11.23-GCC-4.8.2.eb b/easybuild/easyconfigs/c/ConcurrentVersionsSystem/ConcurrentVersionsSystem-1.11.23-GCC-4.8.2.eb
index 17149a15e40..871628918c8 100644
--- a/easybuild/easyconfigs/c/ConcurrentVersionsSystem/ConcurrentVersionsSystem-1.11.23-GCC-4.8.2.eb
+++ b/easybuild/easyconfigs/c/ConcurrentVersionsSystem/ConcurrentVersionsSystem-1.11.23-GCC-4.8.2.eb
@@ -15,7 +15,7 @@ description = """CVS is a version control system, an important component of
 toolchain = {'name': 'GCC', 'version': '4.8.2'}
 
 source_urls = [' http://ftp.gnu.org/non-gnu/cvs/source/stable/%(version)s/']
-sources = [SOURCELOWER_TAR_BZ2]
+sources = ['cvs-%(version)s.tar.bz2']
 
 patches = ['CVS-1.11.23-zlib-1.patch', 'CVS-1.11.23-getline.patch']
 
diff --git a/easybuild/easyconfigs/c/ConcurrentVersionsSystem/ConcurrentVersionsSystem-1.11.23-GCCcore-11.2.0.eb b/easybuild/easyconfigs/c/ConcurrentVersionsSystem/ConcurrentVersionsSystem-1.11.23-GCCcore-11.2.0.eb
index c5e05721940..6275858037f 100644
--- a/easybuild/easyconfigs/c/ConcurrentVersionsSystem/ConcurrentVersionsSystem-1.11.23-GCCcore-11.2.0.eb
+++ b/easybuild/easyconfigs/c/ConcurrentVersionsSystem/ConcurrentVersionsSystem-1.11.23-GCCcore-11.2.0.eb
@@ -16,7 +16,7 @@ Source Configuration Management (SCM).
 toolchain = {'name': 'GCCcore', 'version': '11.2.0'}
 
 source_urls = [' https://ftp.gnu.org/non-gnu/cvs/source/stable/%(version)s/']
-sources = [SOURCELOWER_TAR_BZ2]
+sources = ['cvs-%(version)s.tar.bz2']
 patches = [
     'CVS-1.11.23-zlib-1.patch',
     'CVS-1.11.23-getline.patch',
diff --git a/easybuild/easyconfigs/c/ConcurrentVersionsSystem/ConcurrentVersionsSystem-1.11.23-GCCcore-4.9.3.eb b/easybuild/easyconfigs/c/ConcurrentVersionsSystem/ConcurrentVersionsSystem-1.11.23-GCCcore-4.9.3.eb
index 9851a5c0aac..3d594d8f915 100644
--- a/easybuild/easyconfigs/c/ConcurrentVersionsSystem/ConcurrentVersionsSystem-1.11.23-GCCcore-4.9.3.eb
+++ b/easybuild/easyconfigs/c/ConcurrentVersionsSystem/ConcurrentVersionsSystem-1.11.23-GCCcore-4.9.3.eb
@@ -15,7 +15,7 @@ description = """CVS is a version control system, an important component of
 toolchain = {'name': 'GCCcore', 'version': '4.9.3'}
 
 source_urls = [' http://ftp.gnu.org/non-gnu/cvs/source/stable/%(version)s/']
-sources = [SOURCELOWER_TAR_BZ2]
+sources = ['cvs-%(version)s.tar.bz2']
 
 patches = ['CVS-1.11.23-zlib-1.patch', 'CVS-1.11.23-getline.patch']
 
diff --git a/easybuild/easyconfigs/c/ConcurrentVersionsSystem/ConcurrentVersionsSystem-1.11.23-GCCcore-6.4.0.eb b/easybuild/easyconfigs/c/ConcurrentVersionsSystem/ConcurrentVersionsSystem-1.11.23-GCCcore-6.4.0.eb
index e2a7435be31..196d0c4fc1d 100644
--- a/easybuild/easyconfigs/c/ConcurrentVersionsSystem/ConcurrentVersionsSystem-1.11.23-GCCcore-6.4.0.eb
+++ b/easybuild/easyconfigs/c/ConcurrentVersionsSystem/ConcurrentVersionsSystem-1.11.23-GCCcore-6.4.0.eb
@@ -15,7 +15,7 @@ description = """CVS is a version control system, an important component of
 toolchain = {'name': 'GCCcore', 'version': '6.4.0'}
 
 source_urls = [' http://ftp.gnu.org/non-gnu/cvs/source/stable/%(version)s/']
-sources = [SOURCELOWER_TAR_BZ2]
+sources = ['cvs-%(version)s.tar.bz2']
 patches = [
     'CVS-1.11.23-zlib-1.patch',
     'CVS-1.11.23-getline.patch',