They were: Doctor John Marsden, Doctor Ian Ragan and Doctor Simon Campbell.

Entity and relation annotations:
id: 0
type: entity
value: text: Doctor
labels: <Title>
id: 1
type: entity
value: text: John Marsden
labels: <Person>
id: 2
type: entity
value: text: Doctor
labels: <Title>
id: 3
type: entity
value: text: Doctor
labels: <Title>
id: 4
type: entity
value: text: Ian Ragan
labels: <Person>
id: 5
type: entity
value: text: Simon Campbell
labels: <Person>
type: relation
to_id: 0
labels: Person:holds_title:Title
from_id: 1
type: relation
to_id: 2
labels: Person:holds_title:Title
from_id: 4
type: relation
to_id: 3
labels: Person:holds_title:Title
from_id: 5