Editorial Note

Most of the research papers presented here are more than a decade old. In my attempt to edit these documents, I tried to preserve the original text as much as possible. Apart from correcting typos and unfortunate wording I left the text unchanged. Whenever I found a section that seemed outdated or in need of complementation I added a paragraph in

[2013] a different type of font prepended with the year in brackets

to append thoughts that are helpful to put the original statements in perspective based on today's knowledge.

Many original links are not functional today. I tried to recreate the material I've linked to from files I stored at the time or I replaced the links with what I found on the internet at a different URL. In any case I don't intend to claim any copyright ownership on material I make available in the "legacy" section of this research section.

If any of the original authors feel unhappy with their material being stored in the legacy section, please complain, and I will remove the files on request after having checked the authenticity of the complainant.