diff --git a/src/14_doping_and_devices_solutions.md b/src/14_doping_and_devices_solutions.md
index 5811e68b0746855e4ccb91beffb80d7e42e5293d..53c60ef79f372c1d05cef25aeb126281be16adf7 100644
--- a/src/14_doping_and_devices_solutions.md
+++ b/src/14_doping_and_devices_solutions.md
@@ -5,7 +5,7 @@ from math import pi
 ```
 # Solutions for lecture 14 exercises
 
-## Exercise 1: Crossover between extrinsic and intrinsic regimes
+## Exercise 1: Crossover between extrinsic and intrinsic regimes 
 
 ### Subquestion 1
 Law of mass action: