I would like to offer my personal condolences and those of the italian gnomonic community. My father died on April 01 of 4 years ago. That strange coincidence! I consider Fer as one of my gnomonic fathers. Indeed Fer de Vries was among the first to publish a free software for calculation of sundials, and was among the first to disclose the calculation algorithm. Thanks to him I was able to realize many years ago my first program in Basic. Fer was the pioneer of algorithms based on vector algebra, and through this method, others after him, were able to calculate sundials ever more complex. Thanks Fer for being existed! Now it's up to us to make sure that your track in this world is not forgotten. It would be nice for the whole gnomonic community in the world whether the Dutch gnomonic society would gather and publish all his gnomonic opera. As editor of the magazine Orologi Solari I assure our full collaboration. My best salutation to all. Luigi Ghia
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