Grossman, Anna Jane (2010-03-20). "The Life and Death of the Rolodex". Gizmodo . Retrieved 2022-08-21. Card indexes and the card index boxes come in different sizes, but common sizes include 3x5in 127x76mm, 4x6in 152x102mm and 5x8in 203x127mm. Our record cards are available in white and assorted colours as well as both plain and ruled record cards.

USpatent 2731966A,Neilsen, Hildaur L.,"Rotary card-filing device",issued 1956-01-24, assigned to Zephyr American Corporation . Fascinating facts about the invention of Rolodex by Hildaur Neilsen in 1954". 2006-06-09. Archived from the original on 2010-12-17 . Retrieved 2014-09-04.Nguyen, Bang Dang (2012-02-01). "Does the Rolodex Matter? Corporate Elite's Small World and the Effectiveness of Boards of Directors". Management Science. 58 (2): 236–252. doi: 10.1287/mnsc.1110.1457. ISSN 0025-1909. The Rolodex was invented in 1956 by Danish engineer Hildaur Neilsen, the chief engineer of Arnold Neustadter's company Zephyr American, a stationery manufacturer in New York. [7] Neustadter was often credited with having invented it. [8] [9] First marketed in 1958, [10] it was an improvement to an earlier design called the Wheeldex. Zephyr American also invented, manufactured and sold the Autodex, a spring-operated phone directory that automatically opened to the selected letter; Swivodex, an inkwell that did not spill; Punchodex, a paper hole puncher; and Clipodex, an office aid that attached to a stenographer's knee. [11] [12] Perlman, Merrill (2020-04-16). " 'Rolodex,' on rotation". Columbia Journalism Review . Retrieved 2022-08-21.

Nissen, Mark E.; Sawy, Omar A. (2002-09-01). The Rolodex Model: Understanding Relationship Complexity as a Precursor to the Design of Organizational Forms for Chaotic Environments (Technical report). Monterey, CA: Naval Postgraduate School. Bellis, Mary. "History of the Rolodex - Hildaur Neilson invented the Rolodex". Archived from the original on 2008-11-07 . Retrieved 2014-09-04. Place your index cards inside the card index holders and benefit from colour-coded guide cards that are often indexed alphabetically A-Z to stand out. Engelberg, Joseph; Gao, Pengjie; Parsons, Christopher A. (2013). "The Price of a CEO's Rolodex". Review of Financial Studies. 26: 79–114. CiteSeerX 10.1.1.825.7702. doi: 10.1093/rfs/hhs114 . Retrieved 2022-08-21.

Lasker, David (1990-01-28). "ICONS: Rolodex: A Rotary File Comes Full Circle". Los Angeles Times . Retrieved 2022-08-21. Arnold Neustadter, 85, who invented the Rolodex card..." Baltimore Sun. 1996-04-20 . Retrieved 2022-08-21.