diff --git a/.github/workflows/makefile.yml b/.github/workflows/makefile.yml
index 37fb2e5..e4aefe6 100644
--- a/.github/workflows/makefile.yml
+++ b/.github/workflows/makefile.yml
@@ -13,8 +13,8 @@ jobs:
       uses: actions/checkout@v3.5.0
     - name: Install requirements
       run: |
-        sudo sed -i -e '$adeb http://archive.ubuntu.com/ubuntu trusty main restricted universe multiverse' /etc/apt/sources.list
-        sudo sed -i -e '$adeb http://security.ubuntu.com/ubuntu trusty-security main restricted universe multiverse" /etc/apt/sources.list
+        echo 'deb http://archive.ubuntu.com/ubuntu trusty main restricted universe multiverse' | sudo tee -a /etc/apt/sources.list
+        echo 'deb http://security.ubuntu.com/ubuntu trusty-security main restricted universe multiverse"' | sudo tee -a /etc/apt/sources.list
         sudo apt-get update 
         sudo apt-get install gfortran-5
     - name: Make & install