sentences:  As is well known, in order to express indistinguishability, the particles are deemed to be "individuals", say by attaching them to coordinates or to adequate functions/vectors like |ψ>.Thus, given two quantum systems labeled |ψ12121221
  
  Kitty Hawk Aircargo
  
  "For the Dallas, Texas, based airline that flew in 1978, see Kitty Hawk Airways.