Help with duplicate fields using joins

[#1]

Hi guys,

I have two tables whrere am outer joining one with the other but the problem is it is giving a result like below where if a person belows to External it duplicates the record with an empty on but if they below to BSERVE then its fine

Source

BSERVE

INTERNAL

source ID	ITYPE
22	External
22
34	BSERVE
36	BSERVE
37	External
37

any ideas?

thanks