I'm running Ubuntu 12.04, and two active linux images 3.2.0-37 and 3.2.0-36. In the /usr/src/ directory i find:

linux-headers-3.2.0-23    

linux-headers-3.2.0-23-generic    

linux-headers-3.2.0-26    

linux-headers-3.2.0-26-generic

linux-headers-3.2.0-29    

linux-headers-3.2.0-29-generic

linux-headers-3.2.0-31    

linux-headers-3.2.0-31-generic    

linux-headers-3.2.0-32    

linux-headers-3.2.0-32-generic    

linux-headers-3.2.0-33    

linux-headers-3.2.0-33-generic    

linux-headers-3.2.0-34    

linux-headers-3.2.0-34-generic    

linux-headers-3.2.0-35    

linux-headers-3.2.0-35-generic    

linux-headers-3.2.0-36    

linux-headers-3.2.0-36-generic     

linux-headers-3.2.0-37     

linux-headers-3.2.0-37-generic

Today I sudo apt-get purge linux-image-x.x.x.x-generic *34 and *35

I have to add that /boot contains only *36 and *37.

Is it safe to remove all of these except *37 and *36 ? Thank you in advance.