# [Tex/LaTex] Writing a sequence of maps properly

arrows

I wanna write the sequence $L \underset{\beta_1} \leftrightarrows \overset{ \alpha_1} M \underset{\alpha_2} \leftrightarrows \overset{ \beta_2} N$

with the map \alpha_1 above the arrows and \beta_1 below the arrows, same goes for \alpha_2 and \beta_2.

\documentclass{standalone}
$L \underset{\beta_1}{\overset{ \alpha_1} \leftrightarrow} M \underset{\alpha_2}{\overset{ \beta_2} \leftrightarrow} N$