looks like a nobile type..
have a look at this
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General Care
Dendrobium Species Culture
Margit, I am not saying that this is a yamamotto Yellow Song 'Canary', only that it looks similar to it.
Can't really tell from the pix but I presume all the flowers are blooming from old leafless canes.
Also the some of the leaves are very yellow, though if it is on last year growth it should be ok as they would natually yellow and fall off.
FYI.
This is the yearly cycle of nobiles.
Year one -> new growth canes
Year two -> leaves on last year's canes yellows and drops. Then buds forms on on the opposite side of where the leaves were and blooms. Ater blooming you should notice new growth from the base of the plant again repeating the cycle.
Year three -> the spent canes is now old back canes, don't cut it off as sometimes it blooms again from unbudded nodes and it is also a source of nutrients for the current growths.