$ sudo apt-get update
$ sudo apt-get install liblablgtk2-ocaml 

liblablgtk2-ocaml is installed in your system.

Make ensure the liblablgtk2-ocaml package were installed using the commands given below,

$ sudo dpkg-query -l | grep liblablgtk2-ocaml *

You will get with liblablgtk2-ocaml package name, version, architecture and description in a table

liblablgtk2-ocaml package basic information: