1. Abe H, Sato-Okoshi W, Tanaka M, Okoshi K, Teramoto W, Kondoh T, Nishitani G, Endo Y (2014) Swimming behavior of the spoon worm Urechis unicinctus (Annelida, Echiura). Zool 117: 216–223.
2. Anker A, Murina GV, Lira C, Vera Caripe JA, Palmer AR, Jeng MS (2005) Macrofauna associated with echiuran burrows: a review with new observations of the innkeeper worm, Ochetostoma erythrogrammon Leuckart and Rüppel, in Venezuela. Zool Stud 44: 157–190.
3. Boxshall GA (1990) Precopulatory mate guarding in copepods. Bijdr Dierk 60: 209–213.
4. Boxshall GA, Defaye D (2008) Global diversity of copepods (Crustacea: Copepoda) in freshwater. Hydrobiologia 595: 195–207.
5. Boxshall GA, Humes AG (1987) A new species of Hemicyclops (Copepoda: Poecilostomatoida) associated with an echiuran worm in Hong Kong. Asian Mar Biol 4: 61–66.