From the article:

The format dd.mm.yyyy using dots (which denote ordinal numbering) is the traditional German date format. Since 1996-05-01, the international format yyyy-mm-dd has become the official standard date format, but the handwritten form d. mmmm yyyy is also accepted (see DIN 5008). Standardisation applies to all applications in the scope of the standard including uses in government, education, engineering and sciences. Since 2006, the old format (d)d.(m)m.(yy)yy is allowed again as alternative to the yyyy-mm-dd format in areas where there is no risk of ambiguation.