If you are citing several works published by the same author in the same year, use lower case letter directly after the year to separate them. The same year-letter combination is used in both the in-text reference and the reference list.
| Parenthetical citation | Narrative citation |
|---|---|
| (Ljungberg, 2002a, 2002b) | Ljungberg (2002a, 2002b) has investigated the habitat needs of threatened ground living beetle species in Sweden… |
Ljungberg, H. (2002a). Bete, störning och biologisk mångfald i odlingslandskapet: Hotade skalbaggar i öländska torrmarker [Grazing, disturbance and biodiversity: Threatened beetles in the drylands of Öland] (Meddelande No. 2002:20). Länsstyrelsen Kalmar län.
Ljungberg, H. (2002b). Våra rödlistade jordlöpares habitatkrav [Important habitats for red-listed ground beetles in Sweden]. Entomologisk tidskrift, 123(4), 167-185.