Bd. 1. 1843
http://books.google.com/books?id=PT1-rNyu5BoC
http://books.google.com/books?id=UfdBAAAAIAAJ
http://books.google.com/books?id=KjEzv7F2rtoC
http://books.google.com/books?id=ARo6AAAAcAAJ
https://archive.org/details/lifeandtimespet00campgoog
http://hdl.handle.net/2027/uc2.ark:/13960/t46q23c98
http://hdl.handle.net/2027/uc1.$b65457
http://hdl.handle.net/2027/hvd.32044004617916
http://hdl.handle.net/2027/uva.x004440146
Bd. 2. 1843
http://books.google.com/books?id=-PZBAAAAIAAJ
http://books.google.com/books?id=wNMOAAAAIAAJ
http://books.google.com/books?id=yTmcw34pLYYC
http://books.google.com/books?id=HBo6AAAAcAAJ
https://archive.org/details/lifetimesofpetra01camp
https://archive.org/details/lifetimesofpetra02camp
https://archive.org/details/lifeandtimespet01campgoog
http://hdl.handle.net/2027/uc2.ark:/13960/t16m3cs42
http://hdl.handle.net/2027/uc1.$b65458
http://hdl.handle.net/2027/uva.x000196884
http://hdl.handle.net/2027/hvd.32044004773651
Bd. 1. 1843
http://books.google.com/books?id=PT1-rNyu5BoC&pg=PR21
https://archive.org/stream/lifeandtimespet00campgoog#page/n24
http://hdl.handle.net/2027/uc1.$b65457?urlappend=%3Bseq=27
Bd. 2. 1843
http://books.google.com/books?id=-PZBAAAAIAAJ&pg=PR3
https://archive.org/stream/lifetimesofpetra01camp#page/n13
http://hdl.handle.net/2027/uc2.ark:/13960/t16m3cs42?urlappend=%3Bseq=15