thecpaptain@Anna:~/Downloads$ dpkg --list | grep -E "\sop-"
ii  op-boole                                  3.2-1                                  all          An aid for creating truth-tables
ii  op-fitch                                  3.3-0                                  all          A tool for building formal proofs
iU  op-jre                                    1.5.0-22                               i386         Customized Java JRE for use with OpenProof Software
ii  op-lpl-common                             12.10-0                                all          Common files for the LPL software package
ii  op-lpl-doc                                12.10-0                                all          Documentation for the LPL software package
ii  op-submit                                 3.0-2                                  all          An application for submitting openproof exercises for grading
ii  op-tarski                                 7.0-1                                  all          An environment for evaluating sentences of first order logic
thecpaptain@Anna:~/Downloads$