Lightweight implementation of Hummingbird cryptographic algorithm on 4-bit microcontrollers. - Xinxin Fan; Honggang Hu; Guang Gong; Eric M. Smith; Daniel W. Engels (ICITST, 2009)

Hummingbird: Ultra-Lightweight Cryptography for Resource-Constrained Devices. - Daniel W. Engels; Xinxin Fan; Guang Gong; Honggang Hu; Eric M. Smith (Financial Cryptography Workshops, 2010)

A lightweight privacy-preserving mutual authentication protocol for RFID systems. - Xinxin Fan; Guang Gong; Daniel W. Engels; Eric M. Smith (GLOBECOM Workshops, 2011)

The Hummingbird-2 Lightweight Authenticated Encryption Algorithm. - Daniel W. Engels; Markku-Juhani O. Saarinen; Peter Schweitzer; Eric M. Smith (IACR Cryptol. ePrint Arch., 2011)