In response to statistical problems of  T. Mehner:
A good bock in German language is: Angewandte Statistik fuer
Naturwissenschaftler", written by Lozan, J., published in Parey's
Studientexte. In chapter 8 you will find a good, detailed but also easy to
understand explanation for comparing linear regressions.
Good luck,
Philipp Fischer

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Dr. Philipp Fischer                                                    Tel:
++49 7531 88-4536
Limnologisches Institut                                              Fax:
++49 7531 88-3688     
Universität Konstanz
e-mail: [log in to unmask]
Mainaustr.212
78434 Konstanz
Germany
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