Crocus species

I'm not sure about the species of these Crocuses. If you happen to know, please tell me, too.

Photo: Crocus 0. Flowering plants. Helsinki, Finland. Planted. 2000-04-18.	Photo: Crocus 1. 'Yellow mammoth'. Flowers. Tapanila, Helsinki, Finland. Planted. 2010-04-26.	Photo: Crocus 2. 'Yellow mammoth'. Flowers. Tapanila, Helsinki, Finland. Planted. 2010-04-26.	Photo: Crocus 3. Flowering plant. Tapanila, Helsinki, Finland. Planted. 2011-04-23.
Photo: Crocus 4. Flowering plants. Tapanila, Helsinki, Finland. Planted. 2011-04-23.	Photo: Crocus 5. Flower. Tapanila, Helsinki, Finland. Planted. 2011-04-23.	Photo: Crocus 6. Flowering plants. Tapanila, Helsinki, Finland. Planted. 2011-04-24.

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