... Almeida¹

The first author received support from the Center for Research and Development in Mathematics and Applications (CIDMA) through the Portuguese Foundation for Science and Technology (FCT—Fundação para a Ciência e Tecnologia), reference UIDB/04106/2020.

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... Cardoso²

The second author received support from the Portuguese Foundation for Science and Technology (FCT—Fundação para a Ciência e Tecnologia, reference PD/BD/150533/2019).

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