“…Interestingly, though, not all instances of [@] can alternate with zero-for example, the schwa in words such as [íg@r j ] is always present. Identifying the conditions that affect the realization of yer vowels has become a perennial problem in Slavic phonology (Lightner 1972, Rubach 1986, Kenstowicz and Rubach 1987, Czaykowska-Higgins 1988, Szpyra 1992, Yearley 1995, Zoll 1996, Hermans 2002, Matushansky 2002, Steriopolo 2007, Jarosz 2008, but the pattern shares notable similarities with vowel-zero alternations in unrelated languages such as Itelmen (Bobaljik 1997), Hungarian (Siptár and Törkenczy 2000), and Salish languages (Kinkade 1997, van Eijk 1997, Blake 2001, Rowicka 2002, Gouskova 2003.…”