@article {Zuffardi-Comerci1931,
	title = {Paleontologia della Somalia. Parte 2, numero 2. Fossili del Giuralias: Corallari e idrozoi del giuralias della Somalia},
	journal = {Palaeontographia Italica},
	volume = {32},
	number = {2},
	year = {1931},
	pages = {49{\textendash}76},
	keywords = {RCBS, TIP},
	author = {Zuffardi-Comerci, R}
}
@article {Yabe1931,
	title = {A study of Recent and semifossil corals of Japan: 1. Antillia and 2. Caulastraea},
	journal = {Science Reports of the T{\^o}hoku Imperial University, Second Series (Geology)},
	volume = {14},
	number = {2A},
	year = {1931},
	pages = {119{\textendash}133},
	url = {http://ci.nii.ac.jp/naid/110004624571/en},
	author = {Yabe, Hisakatsu and Sugiyama, Toshio}
}
@article {Zuffardi-Comerci1931a,
	title = {Paleontologia della Somalia. Parte 3, numero 4. Fossili del Cretaceo: Corallari del Cretaceo della Somalia},
	journal = {Palaeontographia Italica},
	volume = {32},
	number = {2},
	year = {1931},
	pages = {209{\textendash}216},
	keywords = {RCBS, TIP},
	author = {Zuffardi-Comerci, R}
}
@article {Richter1931,
	title = {Geologische F{\H u}hrer durch die Zarnglaff-Schwanteschagener Malmbruche},
	journal = {Mitteilungen aus dem Geologisch-Pal{\"a}ontologischen Institut der Universit{\"a}t Greifswald},
	volume = {7},
	year = {1931},
	pages = {3{\textendash}214},
	keywords = {JS, TIP},
	author = {Richter, K}
}
@article {Renz1931,
	title = {Zur Kenntnis der Gattung Aspidiscus Koenig},
	journal = {M{\'e}moires de la Soci{\'e}t{\'e} Pal{\'e}ontologique Suisse},
	volume = {51},
	year = {1931},
	pages = {1{\textendash}6, pl. 1},
	keywords = {RCBS, TIP},
	author = {Renz, C}
}
@article {Parona1931,
	title = {Paleontologia della Somalia (2). Fossili del Giuralias (3). "Somalica Aenigmatica": fossilis incertae saedis},
	journal = {Palaeontographia Italica},
	volume = {32},
	number = {S2},
	year = {1931},
	pages = {77{\textendash}80},
	keywords = {RCBS, TIP},
	author = {Parona, C F and Zuffardi-Comerci, R}
}
@article {Cottreau1931a,
	title = {Types du prodrome de pal{\'e}ontologie stratigraphique universelle},
	journal = {Annales de Pal{\'e}ontologie (Invert{\'e}br{\'e}s)},
	volume = {20},
	number = {3/4},
	year = {1931},
	pages = {173{\textendash}192, pl. 62{\textendash}65},
	keywords = {BL, TIP},
	author = {Cottreau, J}
}
@article {Cottreau1931,
	title = {Types du prodrome de pal{\'e}ontologie stratigraphique universelle},
	journal = {Annales de Pal{\'e}ontologie (Invert{\'e}br{\'e}s)},
	volume = {20},
	number = {1},
	year = {1931},
	pages = {133{\textendash}172, pl. 58{\textendash}61},
	keywords = {BL, TIP},
	url = {http://1drv.ms/1JCvkg4},
	author = {Cottreau, J}
}
@article {Collignon1931,
	title = {La faune du C{\'e}nomanien {\`a} fossiles pyriteux du nord de Madagascar},
	journal = {Annales de Pal{\'e}ontologie (Invert{\'e}br{\'e}s)},
	volume = {20},
	year = {1931},
	pages = {41{\textendash}104, pl. 2},
	keywords = {RCBS, TIP},
	author = {Collignon, M}
}
