Copyright for all material on the site
is of Christian Lehmann. Anyone may use, but not multiply, this material under condition of mention of the name of the copyright owner and of this site (example of quotation).
Apart from theory and methodology, these pages also contain many facts and data, some with, some without indication of the source. I will be grateful for any corrections, and I hereby express my sincere thanks to those people – too many to be enumerated here – who have helped me improve this site.

Political correctness, gendered language etc.

Over the decades, I have not been able to get convinced that adapting one's language to the requirements implied by the above catchphrases yields tangible benefits for human relations. If anybody should feel offended by my use of words like deaf-mute (instead of currently endorsed hearing impaired) and the like, he [sic!] should rest assured that no disparagement is connoted. Quite on the contrary, the use of euphemisms and other “correct” language conveys that the speaker feels there is a problem with the object (incl. person) designated. The use of straightforward terms has no such implications.

Searching these pages
To the extent that Google has crawled this site, one can search it by using the ‘Suchen’ button on the home page.
Technical notes
Screen display
Screen layout is designed for full-screen display at a resolution of 1024 x 768 pixels. You may gain vertical space by pressing the F11 key (and you will see your navigation bars again by pressing it again).
The files are hypertext files, not traditional text files. This means they have been designed for use on the screen, not for print. This concerns foremost a multiplicity of links to other files and databases. It also concerns the layout: many graphic presentations do not fit on a sheet of paper. Some information is coded by colors and shading. It gets lost if files are printed with a monochromous printer. Moreover, different browsers make different mistakes in printing the files.
Special characters
The texts are replete with special characters. If you want to see them, a unicode font must be installed. This website guarantees this by downloading the font Noto from Google.
For technical reasons, no special characters are used in certain popup definitions. The emergency solution used here for their replacement is unsatisfactory and not recommended for imitation.