Coins, banknotes and other objects are usually refered by an abreviation and eventually a number too, meaning the book or catalogue, and the entry where they are described.
This is the alphabetic listing of references used on this blog:
AG - Gomes, Alberto
Moedas Portuguesas e do Território que Hoje é Portugal, 5th Ed, ANP, Lisbon, 2008
CP - Pascoal, Carlos
Fichas da Madeira, 1792 - 1920, Numisma, Lisbon, 1988
Gomes -
see AG
KM - Krause, Chester and Mishler, Clifford
Standard Catalog of World Coins, 5 Vols, Krause Publ, USA, 1972 - 2008
Pascoal -
see CP
Pik -
Standard Catalogue of World Banknotes, 3 Vols., Krause Publ., USA
SP - Salgado, Jaime and Pascoal, Carlos
Fichas Coloniais Portuguesas, Numisma, Lisbon, 1989
Vital - Vital, Nestor
Pecúnias, Tésseras e Cédulas Madeirenses,