@incollection{khnel1987earthly,
  author = {Kühnel, Bianca},
  title = {From the Earthly to the Heavenly Jerusalem. Representation of the Holy City in Christian Art of the First Millennium},
  year = {1987},
  pages = {34-38, 138-167, 174-177, 220-265, 275-279}
}

@incollection{beckingham1983between,
  author = {Beckingham, Charles F.},
  title = {Between Islam and Christendom. Travellers, Facts and Legends in the Middle Ages and the Renaissance},
  year = {1983},
  volume = {175},
  pages = {1-4}
}