  We have studied theoretically the tunneling between two edges of Quantum Hall
liquids (QHL) of different filling factors, $\nu_{0,1}=1/(2 m_{0,1}+1)$, with
$m_0 \geq m_1\geq 0$, through two separate point contacts in the geometry of
Mach-Zehnder interferometer [Y. Ji et al., Nature {\bf 422}, 415 (2003); I.
Neder et al., Phys.\ Rev.\ Lett. {\bf 96}, 016804 (2006)]. The quasi-particle
formulation of the interferometer model is derived as a dual to the initial
electron model, in the limit of strong electron tunneling reached at large
voltages or temperatures. For $m\equiv 1+m_{0}+m_{1}>1$, the tunneling of
quasiparticles of fractional charge $e/m$ leads to non-trivial $m$-state
dynamics of effective flux through the interferometer, which restores the
regular "electron" periodicity of the current in flux despite the fractional
charge and statistics of quasiparticles. The exact solution available for equal
times of propagation between the contacts along the two edges demonstrates that
the interference pattern of modulation of the tunneling current by flux depends
on voltage and temperature only through a common amplitude.
