Collision Theory - Earth Sciences bibliographies - in Harvard style

In-text: (Henderson, 1996)

Your Bibliography: Henderson, T., 1996. Newton's First Law. [online] Physicsclassroom.com. Available at: <http://www.physicsclassroom.com/class/newtlaws/Lesson-1/Newton-s-First-Law> [Accessed 8 March 2015].

In-text: (Henderson, 1996)

Your Bibliography: Henderson, T., 1996. Newton's Second Law. [online] Physicsclassroom.com. Available at: <http://www.physicsclassroom.com/class/newtlaws/Lesson-3/Newton-s-Second-Law> [Accessed 8 March 2015].

In-text: (Henderson, 1996)

Your Bibliography: Henderson, T., 1996. Newton's Second Law. [online] Physicsclassroom.com. Available at: <http://www.physicsclassroom.com/class/newtlaws/Lesson-3/Newton-s-Second-Law> [Accessed 8 March 2015].

In-text: (Independent Variable, n.d.)

Your Bibliography: Ncsu.edu. n.d. Independent Variable. [online] Available at: <https://www.ncsu.edu/labwrite/po/independentvar.htm> [Accessed 9 March 2015].

In-text: (Pivit, 1998)

Your Bibliography: Pivit, R., 1998. Drag Forces in Formulas. [online] Sheldonbrown.com. Available at: <http://www.sheldonbrown.com/rinard/aero/formulas.htm> [Accessed 9 March 2015].

In-text: (Independent & Dependent Variables, n.d.)

Your Bibliography: Www2.uncp.edu. n.d. Independent & Dependent Variables. [online] Available at: <http://www2.uncp.edu/home/collierw/ivdv.htm> [Accessed 9 March 2015].