Explore the advanced search functionality on the 'Biblioteca Digital da FLUP' website. Identify the available search fields and filters that a user can apply to refine their search for publications. Specifically, list the different criteria or categories that can be used for advanced searching.
Navigate to 'http://ler.letras.up.pt'. Click on the dropdown menu (ID 34) to reveal navigation options. Click on 'Pesquisa Avançada' (ID 47). On the 'Pesquisa Avançada' page, identify all available search fields, filters, or criteria for refining a search. List the identified search criteria or categories.
The agent successfully navigates to the 'Pesquisa Avançada' page. The agent identifies and lists the search fields or filters available on the 'Pesquisa Avançada' page, such as 'Título' (Title), 'Autor' (Author), 'Assunto' (Subject), 'Data de Publicação' (Publication Date), 'Tipo de Documento' (Document Type), and 'Coleção' (Collection).