Pullée, Caroline. (1990) 20th century jewellery. London : Apple. This publication includes a whole page with jewellery attributed to Sybil Dunlop but the circular brooch (top) and earrings are works that should have been attributed to Dorrie Nossiter.
The distinction between the styles is clear when they are laid side by side with Dorrie's leaves being more naturalistic and the overall designs being natural and asymmetrical whereas Sybil's leaves are more stylistic and pieces generally symmetrical.