3cy+: Most birds are possible to sex safely according to the below (based largely on Forsman  and Forsman [in lit.]) but note that any ambiguous individual should be left unsexed.
2cy: In 2cy birds the situation is more difficult; the few birds which show clear male characters should be sexed as such, but since many males have yet to develop these traits, most birds should be left unsexed.
1cy: Not possible to sex according to plumage.
Note 1: Each single character is subject to extensive variation, and sexing should be based on an overall assessment.
Note 2: There are additional sex-related characters, but those presented below are the ones we believe are the most reliable when working with hand-held birds.
Female, 3cy+, September. Most females show only a broad dark subterminal bar to RR, but birds with one additional dark bar are not uncommon (exceptionally, two narrow dark bars may be present). 
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