61_a_history_of_qed
A traditional (and maybe the nicest) version of QED was done at the University of Toronto by Tom Duff, Rob Pike, Hugh Redelmeier, and David Tilbrook; it supports multiple buffers, execution of buffers, and regular expressions with back - referencing.

%3 0061_0001__A A 0061_0002__traditional traditional 0061_0001__A->0061_0002__traditional [attrib] 0061_0004__and and 0061_0004__and->0061_0001__A [conj1] 0061_0006__the the 0061_0004__and->0061_0006__the [conj2] 0061_0005__maybe maybe 0061_0006__the->0061_0005__maybe [qual] 0061_0007__nicest nicest 0061_0006__the->0061_0007__nicest [attrib] 0061_0009__version version 0061_0009__version->0061_0004__and [modifier] 0061_0011__QED QED 0061_0009__version->0061_0011__QED of 0061_0012__was was 0061_0013__done done 0061_0012__was->0061_0013__done [scope] 0061_0013__done->0061_0009__version [arg1] 0061_0015__the_16__University the_University 0061_0013__done->0061_0015__the_16__University at[nim] 0061_0029__and and 0061_0013__done->0061_0029__and by[arg0] 0061_0018__Toronto Toronto 0061_0015__the_16__University->0061_0018__Toronto of 0061_0020__Tom_21__Duff Tom_Duff 0061_0029__and->0061_0020__Tom_21__Duff [conj1] 0061_0023__Rob_24__Pike Rob_Pike 0061_0029__and->0061_0023__Rob_24__Pike [conj2] 0061_0026__Hugh_27__Redelmeier Hugh_Redelmeier 0061_0029__and->0061_0026__Hugh_27__Redelmeier [conj3] 0061_0030__David_31__Tilbrook David_Tilbrook 0061_0029__and->0061_0030__David_31__Tilbrook [conj4]
arc(r_0061_0001__A,r_0061_0002__traditional,attrib).
arc(r_0061_0004__and,r_0061_0001__A,conj1).
arc(r_0061_0004__and,r_0061_0006__the,conj2).
arc(r_0061_0006__the,r_0061_0005__maybe,qual).
arc(r_0061_0006__the,r_0061_0007__nicest,attrib).
arc(r_0061_0009__version,r_0061_0004__and,modifier).
arc(r_0061_0009__version,r_0061_0011__QED,r_0061_0010__of).
arc(r_0061_0012__was,r_0061_0013__done,scope).
arc(r_0061_0013__done,r_0061_0009__version,arg1).
arc(r_0061_0013__done,r_0061_0015__the_r_0061_0016__University,r_0061_0014__at__nim).
arc(r_0061_0013__done,r_0061_0029__and,r_0061_0019__by_arg0).
arc(r_0061_0015__the_r_0061_0016__University,r_0061_0018__Toronto,r_0061_0017__of).
arc(r_0061_0029__and,r_0061_0020__Tom_r_0061_0021__Duff,conj1).
arc(r_0061_0029__and,r_0061_0023__Rob_r_0061_0024__Pike,conj2).
arc(r_0061_0029__and,r_0061_0026__Hugh_r_0061_0027__Redelmeier,conj3).
arc(r_0061_0029__and,r_0061_0030__David_r_0061_0031__Tilbrook,conj4).

n61_a_history_of_qed n61_a_history_of_qed__1_1_1_1_1_1_1 A n61_a_history_of_qed__1_1_1_1_1_2_1_1 traditional n61_a_history_of_qed__1_1_1_1_2_1 -LRB- n61_a_history_of_qed__1_1_1_1_3_1_1 and n61_a_history_of_qed__1_1_1_1_3_2_1_1_1 maybe n61_a_history_of_qed__1_1_1_1_3_2_2_1 the n61_a_history_of_qed__1_1_1_1_3_2_3_1_1 nicest n61_a_history_of_qed__1_1_1_1_4_1 -RRB- n61_a_history_of_qed__1_1_2_1 version n61_a_history_of_qed__1_1_3_1_1 of n61_a_history_of_qed__1_1_3_2_1_1 QED n61_a_history_of_qed__1_2_1 was n61_a_history_of_qed__1_3_1_1 done n61_a_history_of_qed__1_3_2_1_1 at n61_a_history_of_qed__1_3_2_2_1_1 the n61_a_history_of_qed__1_3_2_2_2_1 University n61_a_history_of_qed__1_3_2_2_3_1_1 of n61_a_history_of_qed__1_3_2_2_3_2_1_1 Toronto n61_a_history_of_qed__1_3_3_1_1 by n61_a_history_of_qed__1_3_3_2_1_1_1_1 Tom n61_a_history_of_qed__1_3_3_2_1_1_2_1 Duff n61_a_history_of_qed__1_3_3_2_1_2_1 , n61_a_history_of_qed__1_3_3_2_1_3_1_1_1 Rob n61_a_history_of_qed__1_3_3_2_1_3_1_2_1 Pike n61_a_history_of_qed__1_3_3_2_1_4_1 , n61_a_history_of_qed__1_3_3_2_1_5_1_1_1 Hugh n61_a_history_of_qed__1_3_3_2_1_5_1_2_1 Redelmeier n61_a_history_of_qed__1_3_3_2_1_6_1 , n61_a_history_of_qed__1_3_3_2_1_7_1_1 and n61_a_history_of_qed__1_3_3_2_1_7_2_1_1 David n61_a_history_of_qed__1_3_3_2_1_7_2_2_1 Tilbrook n61_a_history_of_qed__1_4_1 ; n61_a_history_of_qed__1 IP-MAT n61_a_history_of_qed__1_1 NP-SBJ n61_a_history_of_qed__1->n61_a_history_of_qed__1_1 n61_a_history_of_qed__1_2 BED;~cat_Ve_passive_ n61_a_history_of_qed__1->n61_a_history_of_qed__1_2 n61_a_history_of_qed__1_3 IP-PPL-CAT n61_a_history_of_qed__1->n61_a_history_of_qed__1_3 n61_a_history_of_qed__1_4 PUNC n61_a_history_of_qed__1->n61_a_history_of_qed__1_4 n61_a_history_of_qed__1_1_1 NLYR n61_a_history_of_qed__1_1->n61_a_history_of_qed__1_1_1 n61_a_history_of_qed__1_1_2 N n61_a_history_of_qed__1_1->n61_a_history_of_qed__1_1_2 n61_a_history_of_qed__1_1_3 PP n61_a_history_of_qed__1_1->n61_a_history_of_qed__1_1_3 n61_a_history_of_qed__1_1_1_1 NLYR n61_a_history_of_qed__1_1_1->n61_a_history_of_qed__1_1_1_1 n61_a_history_of_qed__1_1_1_1_1 NLYR n61_a_history_of_qed__1_1_1_1->n61_a_history_of_qed__1_1_1_1_1 n61_a_history_of_qed__1_1_1_1_2 PULB n61_a_history_of_qed__1_1_1_1->n61_a_history_of_qed__1_1_1_1_2 n61_a_history_of_qed__1_1_1_1_3 CONJP n61_a_history_of_qed__1_1_1_1->n61_a_history_of_qed__1_1_1_1_3 n61_a_history_of_qed__1_1_1_1_4 PURB n61_a_history_of_qed__1_1_1_1->n61_a_history_of_qed__1_1_1_1_4 n61_a_history_of_qed__1_1_1_1_1_1 D n61_a_history_of_qed__1_1_1_1_1->n61_a_history_of_qed__1_1_1_1_1_1 n61_a_history_of_qed__1_1_1_1_1_2 ADJP n61_a_history_of_qed__1_1_1_1_1->n61_a_history_of_qed__1_1_1_1_1_2 n61_a_history_of_qed__1_1_1_1_1_1->n61_a_history_of_qed__1_1_1_1_1_1_1 n61_a_history_of_qed__1_1_1_1_1_2_1 ADJ n61_a_history_of_qed__1_1_1_1_1_2->n61_a_history_of_qed__1_1_1_1_1_2_1 n61_a_history_of_qed__1_1_1_1_1_2_1->n61_a_history_of_qed__1_1_1_1_1_2_1_1 n61_a_history_of_qed__1_1_1_1_2->n61_a_history_of_qed__1_1_1_1_2_1 n61_a_history_of_qed__1_1_1_1_3_1 CONJ n61_a_history_of_qed__1_1_1_1_3->n61_a_history_of_qed__1_1_1_1_3_1 n61_a_history_of_qed__1_1_1_1_3_2 NLYR n61_a_history_of_qed__1_1_1_1_3->n61_a_history_of_qed__1_1_1_1_3_2 n61_a_history_of_qed__1_1_1_1_3_1->n61_a_history_of_qed__1_1_1_1_3_1_1 n61_a_history_of_qed__1_1_1_1_3_2_1 ADVP n61_a_history_of_qed__1_1_1_1_3_2->n61_a_history_of_qed__1_1_1_1_3_2_1 n61_a_history_of_qed__1_1_1_1_3_2_2 D n61_a_history_of_qed__1_1_1_1_3_2->n61_a_history_of_qed__1_1_1_1_3_2_2 n61_a_history_of_qed__1_1_1_1_3_2_3 ADJP n61_a_history_of_qed__1_1_1_1_3_2->n61_a_history_of_qed__1_1_1_1_3_2_3 n61_a_history_of_qed__1_1_1_1_3_2_1_1 ADV n61_a_history_of_qed__1_1_1_1_3_2_1->n61_a_history_of_qed__1_1_1_1_3_2_1_1 n61_a_history_of_qed__1_1_1_1_3_2_1_1->n61_a_history_of_qed__1_1_1_1_3_2_1_1_1 n61_a_history_of_qed__1_1_1_1_3_2_2->n61_a_history_of_qed__1_1_1_1_3_2_2_1 n61_a_history_of_qed__1_1_1_1_3_2_3_1 ADJS n61_a_history_of_qed__1_1_1_1_3_2_3->n61_a_history_of_qed__1_1_1_1_3_2_3_1 n61_a_history_of_qed__1_1_1_1_3_2_3_1->n61_a_history_of_qed__1_1_1_1_3_2_3_1_1 n61_a_history_of_qed__1_1_1_1_4->n61_a_history_of_qed__1_1_1_1_4_1 n61_a_history_of_qed__1_1_2->n61_a_history_of_qed__1_1_2_1 n61_a_history_of_qed__1_1_3_1 P-ROLE n61_a_history_of_qed__1_1_3->n61_a_history_of_qed__1_1_3_1 n61_a_history_of_qed__1_1_3_2 NP n61_a_history_of_qed__1_1_3->n61_a_history_of_qed__1_1_3_2 n61_a_history_of_qed__1_1_3_1->n61_a_history_of_qed__1_1_3_1_1 n61_a_history_of_qed__1_1_3_2_1 NPR n61_a_history_of_qed__1_1_3_2->n61_a_history_of_qed__1_1_3_2_1 n61_a_history_of_qed__1_1_3_2_1->n61_a_history_of_qed__1_1_3_2_1_1 n61_a_history_of_qed__1_2->n61_a_history_of_qed__1_2_1 n61_a_history_of_qed__1_3_1 DON;~Tn n61_a_history_of_qed__1_3->n61_a_history_of_qed__1_3_1 n61_a_history_of_qed__1_3_2 PP-NIM n61_a_history_of_qed__1_3->n61_a_history_of_qed__1_3_2 n61_a_history_of_qed__1_3_3 PP-LGS n61_a_history_of_qed__1_3->n61_a_history_of_qed__1_3_3 n61_a_history_of_qed__1_3_1->n61_a_history_of_qed__1_3_1_1 n61_a_history_of_qed__1_3_2_1 P-ROLE n61_a_history_of_qed__1_3_2->n61_a_history_of_qed__1_3_2_1 n61_a_history_of_qed__1_3_2_2 NP n61_a_history_of_qed__1_3_2->n61_a_history_of_qed__1_3_2_2 n61_a_history_of_qed__1_3_2_1->n61_a_history_of_qed__1_3_2_1_1 n61_a_history_of_qed__1_3_2_2_1 D n61_a_history_of_qed__1_3_2_2->n61_a_history_of_qed__1_3_2_2_1 n61_a_history_of_qed__1_3_2_2_2 NPR n61_a_history_of_qed__1_3_2_2->n61_a_history_of_qed__1_3_2_2_2 n61_a_history_of_qed__1_3_2_2_3 PP n61_a_history_of_qed__1_3_2_2->n61_a_history_of_qed__1_3_2_2_3 n61_a_history_of_qed__1_3_2_2_1->n61_a_history_of_qed__1_3_2_2_1_1 n61_a_history_of_qed__1_3_2_2_2->n61_a_history_of_qed__1_3_2_2_2_1 n61_a_history_of_qed__1_3_2_2_3_1 P-ROLE n61_a_history_of_qed__1_3_2_2_3->n61_a_history_of_qed__1_3_2_2_3_1 n61_a_history_of_qed__1_3_2_2_3_2 NP n61_a_history_of_qed__1_3_2_2_3->n61_a_history_of_qed__1_3_2_2_3_2 n61_a_history_of_qed__1_3_2_2_3_1->n61_a_history_of_qed__1_3_2_2_3_1_1 n61_a_history_of_qed__1_3_2_2_3_2_1 NPR n61_a_history_of_qed__1_3_2_2_3_2->n61_a_history_of_qed__1_3_2_2_3_2_1 n61_a_history_of_qed__1_3_2_2_3_2_1->n61_a_history_of_qed__1_3_2_2_3_2_1_1 n61_a_history_of_qed__1_3_3_1 P-ROLE;_lgs_ n61_a_history_of_qed__1_3_3->n61_a_history_of_qed__1_3_3_1 n61_a_history_of_qed__1_3_3_2 NP n61_a_history_of_qed__1_3_3->n61_a_history_of_qed__1_3_3_2 n61_a_history_of_qed__1_3_3_1->n61_a_history_of_qed__1_3_3_1_1 n61_a_history_of_qed__1_3_3_2_1 NLYR n61_a_history_of_qed__1_3_3_2->n61_a_history_of_qed__1_3_3_2_1 n61_a_history_of_qed__1_3_3_2_1_1 NLYR n61_a_history_of_qed__1_3_3_2_1->n61_a_history_of_qed__1_3_3_2_1_1 n61_a_history_of_qed__1_3_3_2_1_2 PUNC n61_a_history_of_qed__1_3_3_2_1->n61_a_history_of_qed__1_3_3_2_1_2 n61_a_history_of_qed__1_3_3_2_1_3 CONJP n61_a_history_of_qed__1_3_3_2_1->n61_a_history_of_qed__1_3_3_2_1_3 n61_a_history_of_qed__1_3_3_2_1_4 PUNC n61_a_history_of_qed__1_3_3_2_1->n61_a_history_of_qed__1_3_3_2_1_4 n61_a_history_of_qed__1_3_3_2_1_5 CONJP n61_a_history_of_qed__1_3_3_2_1->n61_a_history_of_qed__1_3_3_2_1_5 n61_a_history_of_qed__1_3_3_2_1_6 PUNC n61_a_history_of_qed__1_3_3_2_1->n61_a_history_of_qed__1_3_3_2_1_6 n61_a_history_of_qed__1_3_3_2_1_7 CONJP n61_a_history_of_qed__1_3_3_2_1->n61_a_history_of_qed__1_3_3_2_1_7 n61_a_history_of_qed__1_3_3_2_1_1_1 NPR n61_a_history_of_qed__1_3_3_2_1_1->n61_a_history_of_qed__1_3_3_2_1_1_1 n61_a_history_of_qed__1_3_3_2_1_1_2 NPR n61_a_history_of_qed__1_3_3_2_1_1->n61_a_history_of_qed__1_3_3_2_1_1_2 n61_a_history_of_qed__1_3_3_2_1_1_1->n61_a_history_of_qed__1_3_3_2_1_1_1_1 n61_a_history_of_qed__1_3_3_2_1_1_2->n61_a_history_of_qed__1_3_3_2_1_1_2_1 n61_a_history_of_qed__1_3_3_2_1_2->n61_a_history_of_qed__1_3_3_2_1_2_1 n61_a_history_of_qed__1_3_3_2_1_3_1 NLYR n61_a_history_of_qed__1_3_3_2_1_3->n61_a_history_of_qed__1_3_3_2_1_3_1 n61_a_history_of_qed__1_3_3_2_1_3_1_1 NPR n61_a_history_of_qed__1_3_3_2_1_3_1->n61_a_history_of_qed__1_3_3_2_1_3_1_1 n61_a_history_of_qed__1_3_3_2_1_3_1_2 NPR n61_a_history_of_qed__1_3_3_2_1_3_1->n61_a_history_of_qed__1_3_3_2_1_3_1_2 n61_a_history_of_qed__1_3_3_2_1_3_1_1->n61_a_history_of_qed__1_3_3_2_1_3_1_1_1 n61_a_history_of_qed__1_3_3_2_1_3_1_2->n61_a_history_of_qed__1_3_3_2_1_3_1_2_1 n61_a_history_of_qed__1_3_3_2_1_4->n61_a_history_of_qed__1_3_3_2_1_4_1 n61_a_history_of_qed__1_3_3_2_1_5_1 NLYR n61_a_history_of_qed__1_3_3_2_1_5->n61_a_history_of_qed__1_3_3_2_1_5_1 n61_a_history_of_qed__1_3_3_2_1_5_1_1 NPR n61_a_history_of_qed__1_3_3_2_1_5_1->n61_a_history_of_qed__1_3_3_2_1_5_1_1 n61_a_history_of_qed__1_3_3_2_1_5_1_2 NPR n61_a_history_of_qed__1_3_3_2_1_5_1->n61_a_history_of_qed__1_3_3_2_1_5_1_2 n61_a_history_of_qed__1_3_3_2_1_5_1_1->n61_a_history_of_qed__1_3_3_2_1_5_1_1_1 n61_a_history_of_qed__1_3_3_2_1_5_1_2->n61_a_history_of_qed__1_3_3_2_1_5_1_2_1 n61_a_history_of_qed__1_3_3_2_1_6->n61_a_history_of_qed__1_3_3_2_1_6_1 n61_a_history_of_qed__1_3_3_2_1_7_1 CONJ n61_a_history_of_qed__1_3_3_2_1_7->n61_a_history_of_qed__1_3_3_2_1_7_1 n61_a_history_of_qed__1_3_3_2_1_7_2 NLYR n61_a_history_of_qed__1_3_3_2_1_7->n61_a_history_of_qed__1_3_3_2_1_7_2 n61_a_history_of_qed__1_3_3_2_1_7_1->n61_a_history_of_qed__1_3_3_2_1_7_1_1 n61_a_history_of_qed__1_3_3_2_1_7_2_1 NPR n61_a_history_of_qed__1_3_3_2_1_7_2->n61_a_history_of_qed__1_3_3_2_1_7_2_1 n61_a_history_of_qed__1_3_3_2_1_7_2_2 NPR n61_a_history_of_qed__1_3_3_2_1_7_2->n61_a_history_of_qed__1_3_3_2_1_7_2_2 n61_a_history_of_qed__1_3_3_2_1_7_2_1->n61_a_history_of_qed__1_3_3_2_1_7_2_1_1 n61_a_history_of_qed__1_3_3_2_1_7_2_2->n61_a_history_of_qed__1_3_3_2_1_7_2_2_1 n61_a_history_of_qed__1_4->n61_a_history_of_qed__1_4_1
( (IP-MAT (NP-SBJ;{TORONTO_QED} (NLYR (NLYR (NLYR (D A;{a})
                                                  (ADJP (ADJ traditional;{traditional})))
                                            (PULB -LRB-)
                                            (CONJP (CONJ and;{and})
                                                   (NLYR (ADVP (ADV maybe;{maybe}))
                                                         (D the;{the})
                                                         (ADJP (ADJS nicest;{nice}))))
                                            (PURB -RRB-)))
                                (N version;{version})
                                (PP (P-ROLE of;{of})
                                    (NP (NPR QED;{QED}))))
          (BED;~cat_Ve_passive_ was;{be})
          (IP-PPL-CAT (DON;~Tn done;{do})
                      (PP-NIM (P-ROLE at;{at})
                              (NP (D the;{the})
                                  (NPR University;{University})
                                  (PP (P-ROLE of;{of})
                                      (NP (NPR Toronto;{Toronto})))))
                      (PP-LGS (P-ROLE;_lgs_ by;{by})
                              (NP (NLYR (NLYR (NPR Tom;{Tom})
                                              (NPR Duff;{Duff}))
                                        (PUNC ,)
                                        (CONJP (NLYR (NPR Rob;{Rob})
                                                     (NPR Pike;{Pike})))
                                        (PUNC ,)
                                        (CONJP (NLYR (NPR Hugh;{Hugh})
                                                     (NPR Redelmeier;{Redelmeier})))
                                        (PUNC ,)
                                        (CONJP (CONJ and;{and})
                                               (NLYR (NPR David;{David})
                                                     (NPR Tilbrook;{Tilbrook})))))))
          (PUNC ;))
  (ID 61_a_history_of_qed))