Achimenes ‘Edouard Otto’, ‘Dr. Kopf and ‘Edmond Boissie’

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Achimenes 'Edouard Otto', 'Dr. Kopf and 'Edmond Boissie'
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This is from the same series as Achimenes ‘Ambroise Verschaffelt’, which is similar to ‘Dr. Kopf’ and ‘Edmond Boissie’.  Could these be from the same cross or series?