diff --git a/Si5351.md b/Si5351.md
index 19e5dfc..d33ae8d 100644
--- a/Si5351.md
+++ b/Si5351.md
@@ -2,6 +2,9 @@
 
 `f_out = f_xtal * p * m * 1/r`
 
-* **p** PLL-Faktor `15.0 <= p <= 90.0`
-* **m** Multisynth-Faktor `6.0 <= m <= 1800.0`
-* **r** Output-Teiler `r = 2 ^ n` für 0 <= n <= 7
\ No newline at end of file
+* **p** PLL-Faktor 
+* **m** Multisynth-Faktor
+* **r** Output-Teiler `r = 2 ^ n` für 0 <= n <= 7
+
+Beispiel Code:
+https://radiotransmitter.wordpress.com/2017/02/23/a-simple-software-to-control-the-si5351a-generator-chip/
\ No newline at end of file