Also called Roman States by Scott, these can be very hard to tell genuine from forgery.
First, if the stamps are not on very shiny-surfaced/glazed paper, they are forgeries. The imperf 40c appears to be on normal colored paper and if so, is a forgery. That said, the commonest forgeries are also on glazed paper.
The horizontal double ruled lines outside the stamps are unbroken on the genuine stamps. Any not so are definitely forgeries. The imperf 40c again shows itself to be a forgery as is the imperf 80c. Obviously if the stamp is cut or perfed so no meeting points can be seen, you can't use that spotting feature.
Genuine perf stamps must measure 13.25, often rough enough to be hard to measure properly. Forgeries are in other gauges but note that there are forgeries in perf 13.
The commonest forgeries used old original printing plates. Stamps with breaks and damage are usually forgeries. See the perfed 2c, 40c and 80c values.
Even the expanded album page image is too small to make accurate determination of stamps not mentioned earlier. You need to examine the stamps and measure the perfs yourself. Be aware that the majority of these issues in collections are forgeries.
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