@techreport{TR-IC-04-08,
  number = {IC-04-08},
  author = {Eduardo Cândido Xavier and Flávio Keide Miyazawa},
  title = {An Approximation Scheme for a One-Dimensional Bin Packing
  Problem with Shelf Divisions},
  month = {August},
  year = {2004}, 
  institution = {Institute of Computing, University of Campinas},
  note = {In English, 10 pages.
    \par\selectlanguage{english}\textbf{Abstract}
       Given bins of size $B$, non-negative values $d$ and $dmax$,
       and a list $L$ of items, each item $e\in L$ with size $s_e$ and
       class $c_e$, we define a shelf as a subset of items packed
       inside a bin with total items size at most $dmax$ such that
       all items in this shelf have the same class. Two subsequent
       shelves must be separated by a shelf divisor of size $d$. The
       size of a shelf is the total size of its items plus the size of
       the shelf divisor.  The Class Constrained Shelf Bin Packing
       Problem consists to pack the items of $L$ into the minimum
       number of bins, such that, the items are divided into shelves
       and the total size of the shelves in a bin is at most $B$.  We
       present an asymptotic approximation scheme for this problem
       where the number of different classes is bounded by a constant
       $C$.  To our knowledge, this is the first approximation result
       where shelves of non-null size are used in packing problems.
  }
}