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Abstract: In this survey paper, we present several results linking quantifier-free axiomatizations of various Euclidean and hyperbolic geometries in languages without relation symbols to geometric constructibility theorems. Several fragments of Euclidean and hyperbolic geometries turn out to be naturally occurring only when we ask for the universal theory of the standard plane (Euclidean or hyperbolic), that can be expressed in a certain language containing only operation symbols standing for certain geometric constructions. [Copyright &y& Elsevier]

We show that Lingenberg’s metric-Euclidean planes are the rectangular planes of Karzel and Stanik which satisfy the axiom “If two of the perpendicular bisectors of a triangle exist, then so does the third”. [ABSTRACT FROM AUTHOR]