# Mean stopping range of $\alpha$-particles in air

I did an experiment in university in which I determined how far $\alpha$-particles emmited from an $Am^{241}$ source penetrate into air. I want to compare my result to literature values but... I cant find any on google! Can somebody point me to a source for this?

Energy of $\alpha$-particles from Am-241 are mostly 5.486 MeV (85.2%) and 5.443 MeV (12.8%).