How do I stop my MySQL query generating two rows for one reference?

I have the following MySQL query which gets all the bookings for an agent, and all the rooms for a booking and performs some simply calculations:

Select a.code, a.name, a.areacode, a.agentgroup, 
  Sum(br.basicprice) As TotalRevenueYTD, 
  Sum(b.adults + b.children + b.infants) As Pax,
  Count(br.bookingref) As Bookings
From booking_record br 
  Inner Join agent a On br.agentref = a.code
  Inner Join bookingroom b On b.bookingref = br.bookingref
Where br.bookingdate > '2011-01-01' And br.bookingdate < Date(Now())
Group By br.agentref

The tables are set out so as a booking_record has 1 agent (agentref -> a.code). An agent may have many bookings, and a booking may have many rooms. In this particular case my revenue and bookings are coming out incorrect because if a single booking has more than 1 room, the row is returned more than once (and as such, the basicprice is counted twice,开发者_JAVA技巧 the booking is counted twice etc).

Any ideas how I can return the correct information?

Thanks, Daniel.

How about?

SELECT a.code, a.name, a.areacode, a.agentgroup
       , Sum(br.basicprice) As TotalRevenueYTD
       , sum(b1.pax) As Pax
       , Count(br.bookingref) As Bookings
FROM booking_record br 
INNER JOIN agent a On br.agentref = a.code 
INNER JOIN (
  SELECT b.bookingref, Sum(b.adults + b.children + b.infants) as pax 
  FROM bookingroom b 
  GROUP BY b.bookingref) AS b1 ON b1.bookingref = br.bookingref
WHERE br.bookingdate >= '2011-01-01' 
  AND br.bookingdate <= Date(Now())
GROUP BY a.code

Note that as @JNK points out, this code is based on the assumption that a.code is a unique or primary key of table agent. If it is it will work correct.
If is is not it will yield indeterminite results.