The substance was detected in extracts from 4 products at trace level in 3 and at low concentration in 1 product

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The substance was detected in extracts from 4 products: at trace level in 3 and at low concentration in 1 product.
Casa Kanela Get low hotel rates and check availability in Quito and hotel reservations at Casa Kanela

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Casa Kanela - Get low hotel rates and check availability in Quito and hotel reservations at Casa Kanela
In 1640 at the age of 13 he took up the study of mathematics

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In 1640, at the age of 13, he took up the study of mathematics.