Before revision: Invention Prototype slotted angle strips were developed by London-based engineer Demetrius Comino in the late 1930s, Darbyshire, Anthony, and Duckworth, Eric (2011), Demetrius Comino: A life and legacy of achievement, Comino Foundation.
After revision: Invention Prototype slotted angle strips were developed by London-based engineer Demetrius Comino in the late 1930s,