@misc{methods+and+apparatus+of+microbiological+nitrification,
    author = {Szydłowska, Jolanta},
    title = {Methods and apparatus of microbiological nitrification},
    address = {Kraków},
    publisher = {<a href=\"http://www.wydawnictwo.pk.edu.pl/\" target=\"_blank\">Wydawnictwo PK</a>},
    date = {2011}
}