cf. steht fuer confer. Auf deutsch 'vgl.'

... and I'm sure there's probably a Latin explanation as to why it is c.f. ... ;)

cf. is an abbreviation for the Latin word confer, meaning "compare with" or "consult". It is mainly used in common and statute law contexts, as well as in academic writing. It is used in binomial nomenclature by placing before the species name to indicate that the species is not confirmed.
I will however confess that I always thought it meant "cross reference" just like Richard. Maybe that's what you learn at school in the UK?

@Richard
cross reference? Bin mir ziemlich sicher, dass bei Zitaten/Quellenangaben cf. im Sinne von confer (lat. conferre-vergleichen) benutzt wird. Was soll denn cross reference in diesem Zusammenhang bedeuten?

@Dan

Inhaltlich stimmt das schon ueberein- cross reference = siehe auch = vergleiche

In der Schule hatten wir das tatsaechlich als 'cross reference' gelernt. 'Confere' ergibt als Wurzel natuerlich mehr Sinn, und erklaert auch wo das 'f' herkommt ;)

confused GB is right !

"confer †4. To bring into comparison, compare, collate. Const. usually with; also to, unto. Also absol. Obs.
(Exceedingly common from 1530 to 1650. The Latin abbreviation ‘cf.’ of confer = compare, is still in use.)"

(source: OED)

Still, c.f. is wrong, cf. is the correct spelling.

With a dot in between the two letters, it means "cantus firmus"...

Yes, reverend, that's right.

But also a) it shouldn't be followed by a comma, and b) it's simply incorrect to use "cf."/"compare" here - it should be "e.g."/"for example".

Sloppily written text (once again).

See:

Siehe auch: Translator's Lament

;-)

Corr.: ;-(