@article {7928,
	title = {Zur Verbreitung von Ambrosia artemisiifolia bei Regensburg},
	journal = {Hoppea},
	volume = {67},
	year = {2006},
	month = {2006///},
	pages = {471 - 484},
	author = {J. Klotz}
}
@article {7929,
	title = {Die Verbreitung von Bidens frondosa bei Regensburg},
	journal = {Hoppea},
	volume = {70},
	year = {2009},
	month = {2009///},
	pages = {105 - 118},
	author = {J. Klotz}
}
@article {7930,
	title = {Breitet sich Ambrosia artemisiifolia im Raum Regensburg weiter aus},
	journal = {Hoppea},
	volume = {70},
	year = {2009},
	month = {2009///},
	pages = {97 - 104},
	author = {J. Klotz}
}
