Zoologisches Zentralblatt (W. Engelmann, 1909)

Zoologisches Zentralblatt (W. Engelmann, 1910)

The Zoologist : a monthly journal of natural history (1913)

Zoology - Packard, A. S. (Alpheus Spring), 1839 -1905 (H. Holt and Co, 1894)

Zoology - Packard, A. S. (Alpheus Spring), 1839 -1905 (Holt, 1892)

Zoology - Packard, A. S. (Alpheus Spring), 1839 -1905 (Holt, 1897)

Zoology - Elliott, Alfred M. (Alfred Marlyn), 1905 -1988 (Appleton-Century-Crofts, 1952)

Zoology; a text-book for universities, colleges and normal schools - Galloway, Thomas Walton, 1866 -1929 (P. Blakiston's son & co, 1922)

Zoology - Lovell, Harvey B. (Harvey Bulfinch) 1904 - (Van Nostrand, 1955)

Zoology - Goodnight, Clarence J. (Clarence James), 1914 -1987 (C. V. Mosby Co, 1954)

Zoology : an elementary text-book - MacBride, E. W. (Ernest William), 1866 -1940 (Univ. Press, 1920)

Zoology for high schools and colleges - Packard, A. S. (Alpheus Spring), 1839 -1905 (H. Holt and Company, 1886)

Zoology for high schools and colleges - Packard, A. S. (Alpheus Spring), 1839 -1905 (H. Holt and Company, 1889)

Zoology for high schools and colleges - Packard, A. S. (Alpheus Spring), 1839 -1905 (H. Holt and Company, 1895)

Zoology for medical students - Kerr, John Graham, 1869 -1957 (Macmillan and co., ltd, 1921)

Zoology, a textbook for college and university students - Chidester, Floyd Earle, 1884 -1947 (D. Van Nostrand, 1932)

Zöology; a textbook for colleges and universities - Cockerell, Theodore D. A. (Theodore Dru Alison), 1866 -1948 (World book company, 1920)

Zoology : a textbook for universities, colleges and normal schools / Thomas Walton Galloway - Galloway, Thomas Walton, 1866 -1929 (Blakiston, 1915)

Известия на Царските природонаучни институти в София = Izvestiia na Tsarskitia prirodonauchni instituti v Sofiia - Tsarskitie prirodonauchni instituti (Sofiia, Bulgaria) (Pechatnitsa P. Glushkov, 1932)

Известия на Царските природонаучни институти в София = Izvestiia na Tsarskitia prirodonauchni instituti v Sofiia - Tsarskitie prirodonauchni instituti (Sofiia, Bulgaria) (Pechatnitsa P. Glushkov, 1942)