Purdue OWL (Online Writing Lab). Here you will find lots of information about academic writing and writing in general. Helpful to search for topics via the "site map''.
UNC handouts (University of North Carolina, Chapel Hill). The University of North Carolina's 'Tips and Tools' are often very thorough and somewhat more extensively described than at Purdue OWL. This site also has a number of short videos, identified by the camera icon.
Manchester Phrase Bank (Academic Phrase bank). This ''bank'' stores thousands of phrases from academic articles. You can find different phrases here and check if your own phrases fit within the register of academic writing. The phrases are arranged thematically, by, for example, "compare and contrast" or "referring to literature.
Utrecht University Library. Here you will find all the help the library offers on writing, literature search, source citation and theses. The LibGuides of the university library give specific advice on searching for literature. They help you evaluate the relevance of sources, how to cite, and how to manage literature.
Effective Strategies for Academic Writing. This site contains a number of forms, examples and theory explained in the accompanying book. You can use them, for example, for formulating main and sub-questions or evaluating your argumentation.