Michael L. answered 02/16/16
Tutor
New to Wyzant
Intuitively explains the concepts in Math and Science
1) Two studies by both Stewart and Brian (2009/2006) & West and Jones (2007/2005) found...
If the article is authored by both Steward and Brian in 2006 and 2009 and the other by West and Jones in 2005 and 2007;
Two studies Steward and Brian(2006, 2009), and West and Jones (2005, 2007) found ...
Two studies (Steward & Brian, 2006, 2009; West & Jones, 2005, 2007) found ...
If the articles were individually authored Steward in 2009, Brian in 2006, West in 2007, Jones in 2005;
Several studies by Steward(2009), Brian(2006), West(2007), and Jones(2005) found ...
Several studies (Steward, 2009; Brian, 2006; West, 2007; Jones, 2005) found ...
2)...evidence which supports their theory (Barnes and Dowes, in 2005, Barnes and Dowes again in 2007, Barnes and Dowes again in 2007. Allister and Brown in 2009, Vanveen and Harrott in 2007. Guthrie, Boggs, Lee and Normands, in 2007,2009,2009,2009).
2)...evidence which supports their theory (Barnes and Dowes, in 2005, Barnes and Dowes again in 2007, Barnes and Dowes again in 2007. Allister and Brown in 2009, Vanveen and Harrott in 2007. Guthrie, Boggs, Lee and Normands, in 2007,2009,2009,2009).
Use letters for publications in the same year to distinguish them, and '&' instead of 'and' inside the parenthesis. Avoid repeating the same authors, just add the publication to them like you did for Gutherie et al.
...evidence which supports their theory (Barnes & Dowes, 2007a, 2007b; Allister & Brown, 2009; Vanveen & Harrott, 2007; Gutherie, Boggs, Lee & Normands, 2007, 2009a, 2009b, 2009c)
3) A number of earlier studies have consistently found similar results (George Graham and Sam perros, 2007. Brian Graham, 2008. Francis Graham and Mary Duncan, 2006, 2006. L. Graham and Mellisa Perry, 2009).
...evidence which supports their theory (Barnes & Dowes, 2007a, 2007b; Allister & Brown, 2009; Vanveen & Harrott, 2007; Gutherie, Boggs, Lee & Normands, 2007, 2009a, 2009b, 2009c)
3) A number of earlier studies have consistently found similar results (George Graham and Sam perros, 2007. Brian Graham, 2008. Francis Graham and Mary Duncan, 2006, 2006. L. Graham and Mellisa Perry, 2009).
Use last names only, if more than one author in the same work, then use the first and second initial of the first author each followed by a period and last name, and last name of the second author. For additional author in a different work include first initial
A number of earlier studies have consistently found similar results (Graham & perros, 2007; Graham, 2008; Graham & Duncan, 2006a, 2006b; Graham & Perry, 2009).
Hope that helps