How to install Mono version >= 3.10.0 on Ubuntu 14.04 LTS?

How to install Mono version >= 3.10.0 on Ubuntu 14.04 LTS?

I installed mono with:

apt-get install mono-complete

but version that come from trusty is is 3.2.8
I follow the installation instructions also form mono-project.com but this result also in version 3.2.8.
I am willing to resolve to compile and install from source as a last choice.

Due to the Ubuntu policies (mainly on product support aspects), its own repository feeds won’t contain latest Mono, but the stable release when each Ubuntu releases were prepared.

To use latest Mono, you must add Xamarin’s feed and use that to install or upgrade,

http://www.mono-project.com/download/#download-lin

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