A. T. Fromhold (1991). „Wave packet solutions“, Quantum Mechanics for Applied Physics and Engineering, Reprint of Academic Press 1981, Courier Dover Publications, გვ. 59 ff. ISBN0486667413. „(p. 61) …the individual waves move more slowly than the packet and therefore pass back through the packet as it advances“
Stefano Longhi, Davide Janner (2008). „Localization and Wannier wave packets in photonic crystals“, რედ. Hugo E. Hernández-Figueroa, Michel Zamboni-Rached, Erasmo Recami: Localized Waves. Wiley-Interscience, გვ. 329. ISBN0470108851.