The derivation of Feynman rules for unparticles carrying standard model quantum numbers is discussed. In particular, this note demonstrates that an application of Mandelstams approach to constructing a gauge-invariant action reproduces for unparticle
s the vertices one obtains through the usual minimal coupling scheme; other non-trivial requirements are satisfied as well. This approach is compared to an alternative method 0801.0892 that has recently been constructed by A. L. Licht.
