Literature cited in text

References and citations of articles and books should be limited to published work or work in press and should be indicated in the text by the name(s) of the author(s) and the year of publication as follow (Higler 1986), (White, Morgan 1999) or to indicate authorship for two authors use ampersand (&) e.g. White&Black (1994); for more than two authors use et al.: (Smith et al. 1989). Papers by the same author published in the same year should be distinguished by small letters of the alphabet added after the year (Marshall 1999a), (Marshall 1998; 1999a,b). Do not use author’s initials text citations unless necessary to distinguish two authors of the same surname.
References to unpublished observations, personal communications, papers in preparation (not in press), should be cited as follow: (E. Wilk-Woźniak, unpublished observations (personal communications, paper in preparation, etc.)). Include all authors in these citations – do not use et al. Don’t list them as references!