source: identify gaps in the information/data already gathered and consider how appropriate data might be sourced, taking into account the practicality and cost of deriving additional information and the utility that such information is likely to offer
target: dynodi bylchau yn yr wybodaeth/data sydd eisoes wedi’u casglu ac ystyried sut gellid canfod data priodol, gan ystyried ymarferoldeb a chost canfod gwybodaeth ychwanegol a’r budd y mae gwybodaeth o’r fath yn debygol o’i olygu