TY  - JOUR 
T1  - Directed hypergraph planarity
JO  - Pesquisa Operacional
A1  - Guedes, André Luiz Pires
A1  - Markenzon, Lilian
SN  - 0101-7438
UL  - 10.1590/S0101-74382005000300005
VL  - 25 
Y1  - 2005
PB  - Brasil 
ER  -