Iona ha Peter Opie
Iona Margaret Balfour Opie (13 Here 1923 – 23 Here 2017) ha Peter Mason Opie (25 Du 1918 – 5 C'hwevrer 1982) a oa ur c'houblad gwerinonourien saoz.
Oberennoù
kemmañ- I Saw Esau: Traditional Rhymes of Youth (1947)
- The Oxford Dictionary of Nursery Rhymes (Oxford University Press, 1951, 2nd edn., 1997), p. 357.
- The Oxford Nursery Rhyme Book (1955)
- Children's Games in Street and Playground (1969)