@article{ElshafieSipman1999,
  author    = {Abdulkader E. Elshafie and Harrie J. M. Sipman},
  title     = {Mediterranean lichens in the tropics : lichens of the mist oasis of Erkwit, Sudan},
  journal   = {Tropical bryology},
  number    = {16},
  pages     = {103 -- 108},
  year      = {1999},
}