At first I'd like to thank http://www.geraldmweinberg.comGerald M. Weinberg for his excellent books, for his useful comments and for the suggestion to start the changes from myself.
I would like to thank http://www.kbi.kiev.ua/ akhavr Andrey V Khavryutchenko, Ruslan Shevchenko, Michael V. Tokarev and http://www.aha.ru/ seriakov George Seriakov for valuable help, comments and criticism. I would like to thank http://mozg.freeservers.com Vladimir Koen-Tsedek for his explanations of language problems; Brian Henderson-Sellers and Paul Herbert for editing of first versions of this paper; Alexander V.Didytch, Alexander Drougov Anton A. Mints, Bohdan Sheptunov and Bernhard Treutwein for useful comments; Simon Cant for the model of the cognitive complexity of software; the members of http://www.aha.ru/ seriakov/SE_page.htm RCSE group for very interesting discussions and experiments.
I would also like to thank all those involved in strange discussions about the nature of software and answered my stupid questions.
Of course big thanks for all people which thought me to understand the human.
I'd like to thank http://www.onestone.deONEstone GmbH and http://www.arbeitsamt.deArbeitsamt Paderborn for two months of rest. This was the time I had analysed the results of my studies and written the papers.
I'd like to thank http://www.psion.comPsion PLC for the excellent design of Psion Series 5. It may be surprising, but the most part of work was done on the computer that can be putted in my pocket.
The text is written in http://www.tug.org LATEX.