1. Locales as spectral spaces

   • Niels Schwartz

   OriginalPaper 15 June 2013 Pages: 1 - 42

2. On essential variables of dual operations and the consequences for operations

   • Sebastian Kerkhoff

   OriginalPaper 01 June 2013 Pages: 43 - 70

3. Fully invariant and verbal congruence relations

   • Clifford Bergman
   • Joel Berman

   OriginalPaper 07 June 2013 Pages: 71 - 94

4. The order of principal congruences of a bounded lattice

   • G. Grätzer

   OriginalPaper 05 June 2013 Pages: 95 - 105