தெறி: திருத்தங்களுக்கு இடையிலான வேறுபாடு

* Carl Kohler, ''A History of Costume'', Dover 1963 reprint, ISBN 0-486-21030-8

* Bryan Bunch, ''The History of Science and Technology'', Houghton Mifflin Books, 2004 ISBN 0-618-22123-9

* [http://www.thedorsetpage.com/history/Button_Making/button_making.htm Worked button making in Dorset]

* [http://www.kk-design.com/scti/in103/students/buttons/button_project/button%20types/types.htm Types of Buttons]

* [http://www.harappa.com/indus2/128.html Button seal]

* [http://www.onefivenine.info/buttons.html Button-making in Birmingham, England in the 1800s]

* [http://www.buttonarium.com Online button museum]