Greist-Bousquet S.; Schiffman H.R. (1981). «The Poggendorff illusion: an illusion of linear extent?». Perception10 (2): 155-64. PMID7279544. doi:10.1068/p100155.
«Real and virtual borders in the Poggendorff illusion». Perception26 (12): 1495-501. 1997. PMID9616477. doi:10.1068/p261495.
Day, R.H. (1973). «The oblique line illusion: The poggendorff effect without parallels». The Quarterly Journal of Experimental Psychology25 (4): 535-541. PMID4767535. doi:10.1080/14640747308400375.
Greist-Bousquet S.; Schiffman H.R. (1981). «The Poggendorff illusion: an illusion of linear extent?». Perception10 (2): 155-64. PMID7279544. doi:10.1068/p100155.
«Real and virtual borders in the Poggendorff illusion». Perception26 (12): 1495-501. 1997. PMID9616477. doi:10.1068/p261495.
Day, R.H. (1973). «The oblique line illusion: The poggendorff effect without parallels». The Quarterly Journal of Experimental Psychology25 (4): 535-541. PMID4767535. doi:10.1080/14640747308400375.