Talvez deva tentar algumas variações de ortografia:
research systems » research synthesis (Expandir a Pesquisa)
medina research » media research (Expandir a Pesquisa), medica research (Expandir a Pesquisa), medical research (Expandir a Pesquisa)
systems dis » systems disk (Expandir a Pesquisa), systems tdis (Expandir a Pesquisa), systems dss (Expandir a Pesquisa)
cent nerve » bent nerve (Expandir a Pesquisa), recent nerve (Expandir a Pesquisa), crest nerve (Expandir a Pesquisa)
nerve vas » nerve a (Expandir a Pesquisa), nerve vi (Expandir a Pesquisa), nerve vii (Expandir a Pesquisa)
i retinal » ii retinal (Expandir a Pesquisa), _ retinal (Expandir a Pesquisa), a retinal (Expandir a Pesquisa)
nerve con » nerve can (Expandir a Pesquisa), nerve cn (Expandir a Pesquisa), nerve co (Expandir a Pesquisa)
j medina » j mejia (Expandir a Pesquisa)
vas dis » vas dias (Expandir a Pesquisa), vasc dis (Expandir a Pesquisa)
a cent » a cento (Expandir a Pesquisa), a cena (Expandir a Pesquisa), a cenp (Expandir a Pesquisa)

You can also try:

• Europeana
• Digital Public Library of America
• CORE

Pode obter mais resultados ajustando a pesquisa.

• Performing a fuzzy search may retrieve terms with similar spellings: (((( a cent nerve vas dis ) or ( i retinal nerve con dos ))) or ( j medina research systems dis ))~.
• Se usar operadores Booleanos, por favor insira-os com letras MAIÚSCULAS: (((( a cent nerve vas dis ) OR ( i retinal nerve con dos ))) OR ( j medina research systems dis )).
• Se adicionar um carácter universal pode recuperar variações da palavra pesquisada: (((( a cent nerve vas dis ) or ( i retinal nerve con dos ))) or ( j medina research systems dis ))*.