References
Johannes Lenhard
(2000-2009)
XAxiomatics without foundations. on the model-theoretical viewpoint in modern axiomatics
2005
Philosophia Scientiae 9/2
Deduction, perception, and modeling
2005
in: Activity and sign, Dordrecht : Springer
Activity and sign: grounding mathematics education2005
with Hoffmann Michael H. G. , Seeger Falk (ed)
Dordrecht, Springer