diff --git a/_fc-versions/calcium.md b/_fc-versions/calcium.md
index 48602203a706d74b1cfa2c443cf8ec0b51d22c49..e671cb3c388651434671510bb09f9692af90eeeb 100755
--- a/_fc-versions/calcium.md
+++ b/_fc-versions/calcium.md
@@ -13,8 +13,10 @@ releases:
         help_link: /html/installations/calcium.html
       - name: User manual
         link: /download/user-manual-20.0-Calcium.pdf
+      - name: Plugin-In development guide
+        link: /download/plugin-development-guide-20.0-Calcium.pdf
         help: Hello plug-in tutorial archive
-        help_link: download/hello-20.0-Calcium.tar.gz
+        help_link: /download/hello-20.0-Calcium.tar.gz
       - name: API Documentation
         link: /download/frama-c-20.0-Calcium-api.tar.gz
       - name: ACSL 1.14 (Calcium implementation)
diff --git a/_fc-versions/potassium.md b/_fc-versions/potassium.md
index 056292f5082a35eb7119798eac4ef12382859015..1c3685c9cf4b3b60b27d935f8364654d74f58fc9 100755
--- a/_fc-versions/potassium.md
+++ b/_fc-versions/potassium.md
@@ -13,8 +13,10 @@ releases:
         help_link: /html/installations/potassium.html
       - name: User manual
         link: /download/user-manual-19.1-Potassium.pdf
+      - name: Plugin-In development guide
+        link: /download/plugin-development-guide-19.1-Potassium.pdf
         help: Hello plug-in tutorial archive
-        help_link: download/hello-19.1-Potassium.tar.gz
+        help_link: /download/hello-19.1-Potassium.tar.gz
       - name: API Documentation
         link: /download/frama-c-19.1-Potassium-api.tar.gz
       - name: ACSL 1.14 (Potassium implementation)
diff --git a/_fc-versions/scandium.md b/_fc-versions/scandium.md
index 7a4165ac941267f84de2fb06c5f6ffea30146fa2..14b152ebc11ddc0250b864e19e025f0dfaf28449 100755
--- a/_fc-versions/scandium.md
+++ b/_fc-versions/scandium.md
@@ -13,8 +13,10 @@ releases:
         help_link: /html/installations/scandium.html
       - name: User manual
         link: /download/user-manual-21.1-Scandium.pdf
+      - name: Plugin-In development guide
+        link: /download/plugin-development-guide-21.1-Calcium.pdf
         help: Hello plug-in tutorial archive
-        help_link: download/hello-21.1-Scandium.tar.gz
+        help_link: /download/hello-21.1-Scandium.tar.gz
       - name: API Documentation
         link: /download/frama-c-21.1-Scandium-api.tar.gz
       - name: ACSL 1.15 (Scandium implementation)