Strony o tunelach w PDF:

http://www.i-b.pl/ib/ib022/ib022s104/ib022s104.pdf

http://www.i-b.pl/ib/ib012/ib012s052/ib012s052.pdf

Mikrotuneling w Power Point:

http://home.agh.edu.pl/~cala/prezentacje/Microtunnelling.pdf

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