Logics of metric spaces.

Oliver Kutz, Holger Sturm, Nobu-Yuki Suzuki, Frank Wolter, and Michael Zakharyaschev 

@Article{	  kutzetal03,
  author	= {O. Kutz AND H. Sturm AND N.-Y. Suzuki AND F. Wolter AND M.
		  Zakharyaschev},
  title		= {Logics of metric spaces},
  journal	= {ACM Transactions on Computational Logic (TOCL)},
  volume	= {4},
  number = {2},
  pages = {260--294},
  year = {2003}
}