[ 1] Y an X F, Ph ilip S Y, H an JW. Graph index ing: Afrequent structure-based approach[ A] . Proceed ing s o fthe 2004 ACM S IGMOD Internationa l Conference onM anag em ent o f Data ( SIGMODc 04 ) [ C ]. Pa ris,Fance: ACM, 2004: 335- 346.
[ 2] Zhang S, HuM, Yang J. T reep:i A nove l graph indexing m ethod[ A]. Proceed ings of the 23rd Interna tionalCon fe rence on Data Eng ineering ( ICDEc07) [ C ].Istanbu,l Turkey: IEEE, 2007: 966- 975.
[ 3] Zhao P X, Yu J X, Yu P S. Graph index ing: tree +de lta> = graph[ A] . Proceedings o f the Internationa lCon ference on Very Large Data Bases ( VLDBc 07 )[ C] . V ienna, Austr ia: ACM, 2007: 938- 949.
[ 4] Fag in R, Lo tem A, NaorM. Optim a l aggrega tion a lgorithm s for m idd lew are [ J]. Journa l of Com pute r andSystem Sciences, 2003, 66( 4) : 614- 656.
[ 5] Chen C, Fredrikson C, Chr istodorescuM. M ining graphpatterns effic iently v ia random ized summ aries[ A]. Proceedings of the International Conference on Very LargeData Bases( VLDBc09) [ C]. Lyon, France: VLDB Endowmen,t 2009: 742- 753.
[ 6] Corde lla LP, Fogg ia P, Sansone C, e t a.l A ( Sub)g raph isom orph ism a lgor ithm form atch ing larg e g raphs[ J] . Journa l of Pattern Ana lysis andM ach ine Inte ll-igence, 2004, 26( 10): 1367- 1372