Talvez deva tentar algumas variações de ortografia:
rats comparing » rates comparing (Expandir a Pesquisa), rate comparing (Expandir a Pesquisa), rcts comparing (Expandir a Pesquisa)
comparing case » comparing cancer (Expandir a Pesquisa), compelling case (Expandir a Pesquisa), comparing climate (Expandir a Pesquisa)
computers can » computers a (Expandir a Pesquisa), computers _ (Expandir a Pesquisa)
computer can » computer case (Expandir a Pesquisa), computer a (Expandir a Pesquisa), computer code (Expandir a Pesquisa)
case now » cases now (Expandir a Pesquisa), case non (Expandir a Pesquisa), case new (Expandir a Pesquisa)
can now » can non (Expandir a Pesquisa), can new (Expandir a Pesquisa), can ngoc (Expandir a Pesquisa)
3 vhdl » _ vhdl (Expandir a Pesquisa), 3 hdl (Expandir a Pesquisa), a vhdl (Expandir a Pesquisa)
j rats » j rath (Expandir a Pesquisa), j raes (Expandir a Pesquisa), rij rats (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: (((( _ units computers can now ) or ( 3 vhdl computer can now ))) or ( j rats comparing case now ))~.
• Se usar operadores Booleanos, por favor insira-os com letras MAIÚSCULAS: (((( _ units computers can now ) OR ( 3 vhdl computer can now ))) OR ( j rats comparing case now )).
• Se adicionar um carácter universal pode recuperar variações da palavra pesquisada: (((( _ units computers can now ) or ( 3 vhdl computer can now ))) or ( j rats comparing case now ))*.