Pentabarf travel

Here is the start of a query for pulling out travel requirements for conference attendees.

SELECT P.last_name, P.first_name,
       CPT.arrival_from,
       CPT.arrival_to,
       CPT.need_accommodation
  FROM conference_person_travel CPT, conference_person CP, conference C, person P
 WHERE CPT.need_accommodation
   AND CPT.conference_person_id = CP.conference_person_id
   AND P.person_id              = CP.person_id
   AND CP.conference_id         = C.conference_id
   AND C.acronym                = 'BSDCan2012'