The definitive reference to the group is Henry Pilsbry's 1940 monograph.
A book based on her thesis was published by Algiers University in 1983 and remains the definitive reference.
The book has become a definitive reference for interpreting the relevance of the Treaty of Waitangi.
The first of the two volume definitive reference on the operas of Handel.
It was immediately recognized as one of the definitive reference works on the subject.
Ms. Gorney's paintings lack such definitive references, relying largely on color to stimulate subjective responses.
There appears to be no current definitive reference for this.
The second of the two-volume definitive reference on the operas of Handel.
This isn't a step towards standardization, says Google, but a step towards creating a definitive reference for the technology.
I believe that, setting aside my opinions, this is the definitive textual reference.