diff --git a/part1/03/03.md b/part1/03/03.md
index cafa79f..d13a706 100644
--- a/part1/03/03.md
+++ b/part1/03/03.md
@@ -15,7 +15,7 @@
     </div>
     <div class="layout-preview">
     <img src="part1/03/distros_timeline.png">
-    <figcaption>Stammbaum der verbreitesten Linux-Distros</figcaption>
+    <figcaption>Stammbaum der verbreitesten Linux-Distros (<a href="https://commons.wikimedia.org/wiki/File:Linux_Distribution_Timeline.svg">Quelle</a>)</figcaption>
     </div>
 </div>
 
@@ -34,7 +34,7 @@
    </div>
    <div class="layout-preview">
    <img src="part1/03/apt.png">
-   <figcaption>Beispiel: apt unter Debian</figcaption>
+   <figcaption>Beispiel: apt unter Debian (<a href="https://commons.wikimedia.org/wiki/File:Apt-get_install_mediawiki.png">Quelle</a>)</figcaption>
    </div>
 </div>
 
@@ -86,6 +86,7 @@
     </div>
     <div class="layout-preview">
     <img src="part1/03/ubuntu.png">
+    <figcaption><a href="https://commons.wikimedia.org/wiki/File:Logo-ubuntu_no(r)-black_orange-hex.svg">Quelle</a></figcaption>
     </div>
 </div>
 
@@ -102,6 +103,7 @@
     </div>
     <div class="layout-preview">
     <img src="part1/03/mint.png">
+    <figcaption><a href="https://commons.wikimedia.org/wiki/File:Linux_Mint_Official_Logo.svg">Quelle</a></figcaption>
     </div>
 </div>
 
@@ -120,6 +122,7 @@
    </div>
     <div class="layout-preview">
     <img src="part1/03/manjaro.png">
+    <figcaption><a href="https://commons.wikimedia.org/wiki/File:Manjaro_logo_text.png">Quelle</a></figcaption>
     </div>
 </div>
 
@@ -134,6 +137,7 @@
     </div>
     <div class="layout-preview">
     <img src="part1/03/suse.png">
+    <figcaption><a href="https://commons.wikimedia.org/wiki/File:OpenSUSE_official-logo-color.svg">Quelle</a></figcaption>
     </div>
 </div>
 
@@ -150,6 +154,7 @@
     </div>
     <div class="layout-preview">
     <img src="part1/03/fedora.png">
+    <figcaption><a href="https://commons.wikimedia.org/wiki/File:Fedora_logo_and_wordmark.svg">Quelle</a></figcaption>
     </div>
 </div>
 
diff --git a/part1/04/04.md b/part1/04/04.md
index cd914b6..049296b 100644
--- a/part1/04/04.md
+++ b/part1/04/04.md
@@ -27,6 +27,7 @@
     </div>
     <div class="layout-preview">
     <img src="part1/04/xerox.png">
+    <figcaption>Benutzeroberfläche des Xerox Alto (<a href="https://commons.wikimedia.org/wiki/File:Smalltalk-76.png">Quelle</a>)</figcaption>
     </div>
 </div>
 
@@ -77,7 +78,7 @@
     </div>
     <div class="layout-preview">
     <img src="part1/04/kubuntu.png">
-    <figcaption>KDE unter Ubuntu (Kubuntu)</figcaption>
+    <figcaption>KDE unter Ubuntu (Kubuntu) (<a href="https://commons.wikimedia.org/wiki/File:Kubuntu_18.10_screenshot.png">Quelle</a>)</figcaption>
     </div>
 </div>
 
@@ -86,16 +87,7 @@
 <div class="layout-preview-only">
 <div class="layout-preview">
 <img src="part1/04/kde_manjaro.png">
-<figcaption>KDE unter Manjaro</figcaption>
-</div>
-</div>
-
----
-
-<div class="layout-preview-only">
-<div class="layout-preview">
-<img src="part1/04/kde_fedora.jpg">
-<figcaption>KDE unter Fedora</figcaption>
+<figcaption>KDE unter Manjaro (<a href="https://commons.wikimedia.org/wiki/File:Manjaro_17.0_Gellivara.png">Quelle</a>)</figcaption>
 </div>
 </div>
 
@@ -114,7 +106,7 @@
 </div>
 <div class="layout-preview">
 <img src="part1/04/gnome_ubuntu.png">
-<figcaption>GNOME unter Ubuntu</figcaption>
+<figcaption>GNOME unter Ubuntu (<a href="https://commons.wikimedia.org/wiki/File:Ubuntu_19.04_"Disco_Dingo".png">Quelle</a>)</figcaption>
 </div>
 </div>
 
@@ -122,17 +114,8 @@
 
 <div class="layout-preview-only">
 <div class="layout-preview">
-<img src="part1/04/gnome_manjaro.jpg">
-<figcaption>GNOME unter Manjaro</figcaption>
-</div>
-</div>
-
----
-
-<div class="layout-preview-only">
-<div class="layout-preview">
-<img src="part1/04/gnome_fedora.png">
-<figcaption>GNOME unter Fedora</figcaption>
+<img src="part1/04/gnome_manjaro.png">
+<figcaption>GNOME unter Manjaro (<a href=https://wikimedia.org/wiki/File:Manjaro_1700_Gnome_1390x698.png">Quelle</a>)</figcaption>
 </div>
 </div>
 
@@ -157,17 +140,8 @@
 
 <div class="layout-preview-only">
 <div class="layout-preview">
-<img src="part1/04/xfce_manjaro.jpg">
-<figcaption>Xcfe unter Manjaro</figcaption>
-</div>
-</div>
-
----
-
-<div class="layout-preview-only">
-<div class="layout-preview">
-<img src="part1/04/xfce_fedora.jpg">
-<figcaption>Xcfe unter Fedora</figcaption>
+<img src="part1/04/xfce_manjaro.png">
+<figcaption>Xcfe unter Manjaro (<a href="https://commons.wikimedia.org/wiki/File:Xfce-170.png">Quelle</a>)</figcaption>
 </div>
 </div>
 
@@ -182,7 +156,7 @@
 </div>
 <div class="layout-preview">
 <img src="part1/04/mate.png">
-<figcaption>MATE unter Ubuntu</figcaption>
+<figcaption>MATE unter Ubuntu (<a href="https://commons.wikimedia.org/wiki/File:MATE_Desktop_Environment_1.8_-_About.png">Quelle</a>)</figcaption>
 </div>
 </div>