was held on November 24-26, 2011 in the Hotel Prezydent in Krynica, Poland.
The meeting was next in the series of wokshops '3in1'
held from 1991 to 2010 in Kraków, Krynica and Kroczyce.
The conference was continuing in the spirit of earlier workshops '3in1',
founded by Professor Zdzisław Skupień.
The main purpose of these meetings is to focus on solving open problems
in combinatorics, mostly in graph
theory.
They provide an invaluable opportunity for informal discussions,
which in former years gave the basis
for getting many new results.
The invited speakers were:
Mieczyslaw Borowiecki, University of Zielona Góra, Poland
Dalibor Froncek, University of Minnesota Duluth, USA
Wilfried Imrich, University of Leoben, Austria
The organizers: Artur Fortuna, Mariusz Meszka,
and Andrzej Żak are greatful to all the partipants for attendance
and making this meeting successful.