Although sentential complementation has been a central concern in syntactic research over the last fifty years, it is often difficult to pinpoint specific studies; often the data is already found in traditional grammars and discussed by many authors. Of course, it is possible to identify several (especially early) seminal studies like Kiparsky & Kiparsky (1970), Bresnan (1972), and Grimshaw (1979), but much of what is found in this (and the following) chapter has been developed over the years by various authors, and it is therefore easier to refer to specific studies during our discussions. Nevertheless, we want to highlight a number of studies we used in our discussion of a number of more special issues. The discussion of factivity in Section 5.1.2 is based on Kiparsky & Kiparsky (1970), supplemented by insights from Barbiers (2000) and Nye (2013). The discussion of reported speech/parenthetical clauses was heavily influenced by Corver (1994), Corver & Thiersch (2003), and De Vries (2006). The discussion of quotative and polar van-constructions has profited a great deal from Van Craenenbroeck (2002), Foolen et al. (2006), and Hoeksema (2006). The discussion of fragment clauses is heavily indebted to the seminal work of Merchant (2001/2006). For a discussion of the independent uses of argument clauses, we refer the reader to De Vries (2001), Verstraete et al. (2012), Tejedor (2013), and Van Linden & Van de Velde (2014).