1. See Barling-Davies-Stratford, p. 89, according to which: “The principle of legal certainty (occasionally referred to as `legal security’), and the closely related principles of legitimate expectation and non-retroactivity, provide useful tools with which to challenge measures which are uncertain or unexpected in their introduction or effects. They concern linked concepts, and are therefore often dealt with together in the literature and case law.”
2. See Usher 1998a, p. 52.
3. Since the information in CELEX is constantly changing, one can verify of the results and establish the current situation easier by referring to the CELEX, http://europa.eu.int/cj/ index.htm.
4. The principle of legal certainty is relatively often used as an argument nowadays, because 37 of those 69 cases, about 54%, were given in the 1990s.
5. On Begriffsjurisprudence, see Aarnio 1989, pp. 115–124.