Groups of particles can interfere with one another; In the double slit experiment when measuring single photons at the screen each one arrives at the screen in a random manner and they only show the interference pattern once several particles are detected.
Obviously two waves can obviously interfere with one another, but can two single particles interfere with one another? Cohen-Tannoudji writes that
light simultaneously behaves like a wave and like a flux of particles
But do two particles constitute a flux of particles? I doubt that this could be tested experimentally but if it were so would this constitute a measurement for each particle?
Here was my thought (Disclaimer:I do not have a good idea of what the interference of two single particle states is): To have interference of two single particles you would have to know something about there position to be able to describe their interference pattern hence the measurement.