Chemical bond in ferroeletric perovskies / Katarzyna TKACZ-ŚMIECH, A. KOLEŻYŃSKI, W. S. PTAK // Ferroelectrics ; ISSN 0015-0193. — 2000 vol. 237 iss. 1, s. 57–64. — Bibliogr. s. 64. — Publikacja dostępna online od: 2011-10-26. — 9th European Meeting on Ferroelectricity (EMF-9) : Prague, Czech Republic, 12–16 July 1999. — tekst: https://www-1tandfonline-1com-15qtywsqb0146.wbg2.bg.agh.edu.pl/doi/pdf/10.1080/00150190008216232

Crystal-chemical aspects of phase transitions in barium titanate / Katarzyna TKACZ-ŚMIECH, Andrzej KOLEŻYŃSKI, W. S. PTAK // Solid State Communications ; ISSN 0038-1098. — 2003 vol. 127 no. 8, s. 557–562. — Bibliogr. s. 562, Abstr.. — tekst: https://www-1sciencedirect-1com-1000027zt02a9.wbg2.bg.agh.edu.pl/science/article/pii/S0038109803005039/pdfft?md5=a43646e972fe3ef24be8384615f82991&pid=1-s2.0-S0038109803005039-main.pdf

Effect of hydrogen on the structure of Si and C clusters formed in gas phase by CVD processes / J. SOBOL-ANTOSIAK, W. S. PTAK // Materials Letters ; ISSN 0167-577X. — 2002 vol. 56 iss. 5 art. no. PII S0167-577X(02)00625-0, s. 842–848. — Abstr.. — tekst: https://www-1sciencedirect-1com-10000272m0183.wbg2.bg.agh.edu.pl/science/article/pii/S0167577X02006250/pdfft?md5=34ecdec453da9d437eba48d2361a92c2&pid=1-s2.0-S0167577X02006250-main.pdf

Effective crystal potential from elecrtonegativity viewpoint / Andrzej KOLEŻYŃSKI, Wiesław S. PTAK, Katarzyna TKACZ-ŚMIECH // International Journal of Quantum Chemistry ; ISSN 0020-7608. — 2003 vol. 91 iss. 3, s. 311–316. — Bibliogr. s. 316, Abstr.. — Publikacja dostępna online od: 2002-11-08. — Ninth international conference on the Application of the density functional theory to chemistry and physics. — tekst: https://onlinelibrary-1wiley-1com-1r3ntz4et0085.wbg2.bg.agh.edu.pl/doi/epdf/10.1002/qua.10388

FTIR studies of structural effects due to boron addition in sintered silicon carbide / E. ERMER, W. S. PTAK // Vibrational Spectroscopy ; ISSN 0924-2031. — 2002 vol. 29 iss. 1–2 art. no. PII S0924-2031(01)00169-2, s. 211–215. — Bibliogr. s. 215, Abstr.. — 1st International conference on Advanced vibrational spectroscopy : Turku, Finland, August 19-24, 2001. — tekst: https://www-1sciencedirect-1com-10000272m013b.wbg2.bg.agh.edu.pl/science/article/pii/S0924203101001692/pdfft?md5=3dce007b4cd1bee0a18c0ec75d2fd5ab&pid=1-s2.0-S0924203101001692-main.pdf

FTIR studies of structural effects of sintered silicon carbide due to boron addition / E. ERMER, W. PTAK // W: ICAVS-1 : the first international conference on Advanced Vibrational Spectroscopy : August 19–24, 2001 Turku, Finland : book of abstracts and program. — Turku : Typopress Oy, 2001. — S. P17.195

Influence of sintering activators on structure of silicon carbide / Elżbieta ERMER, PTAK Wiesław, STOBIERSKI Ludosław // Solid State Ionics ; ISSN 0167-2738. — 2001 vol. 141–142, s. 523–528. — Bibliogr. s. 528, Abstr.. — XIV International Symposium on the Reactivity of Solids : 27-31 August 2000, Budapest

Infrared spectra of $\beta-BaB_{2}O_{4}$ and $LiB_{3}O_{5}$: new nonlinear optical materials / U. MORYC, W. S. PTAK // Journal of Molecular Structure ; ISSN 0022-2860. — 1999 vol. 511–512, s. 241–249. — Bibliogr. s. 248–249, Abstr.. — International conference on vibrational spectroscopy in materials science : 22–25 October 1998, Krakow, Poland. — tekst: https://www-1sciencedirect-1com-1000027u701af.wbg2.bg.agh.edu.pl/science/article/pii/S0022286099001647/pdfft?md5=596c6defbd8810a8287854c6585f934d&pid=1-s2.0-S0022286099001647-main.pdf

Low temperature IR spectra of $a-C:N:H$ layers / S. JONAS, I. ŁAGOSZ, C. PALUSZKIEWICZ, W. S. PTAK // Journal of Molecular Structure ; ISSN 0022-2860. — 2001 vol. 596 iss. 1–3, s. 101–108. — Bibliogr. s. 107–108, Abstr.. — 3rd International Conference of the Vibrational Spectroscopy in Materials Science : 23–26 September 2000, Krakow, Poland. — tekst: https://www-1sciencedirect-1com-1000027wx0102.wbg2.bg.agh.edu.pl/science/article/pii/S0022286001006950/pdfft?md5=38838d70ebd6143af5844bc24a423fad&pid=1-s2.0-S0022286001006950-main.pdf

Pauling's electrostatic rule for partially covalent/partially ionic crystals / K. TKACZ-ŚMIECH, A. KOLEŻYŃSKI, W. S. PTAK // Journal of Physics and Chemistry of Solids ; ISSN 0022-3697. — 2000 vol. 61 iss. 11, s. 1847–1853. — Bibliogr. s. 1853, Abstr.. — Publikacja dostępna online od: 2000-08-30. — tekst: https://www-1sciencedirect-1com-10000276k0252.wbg2.bg.agh.edu.pl/science/article/pii/S0022369700000664/pdfft?md5=547df9a024c86f43c725d3b77b5623ce&pid=1-s2.0-S0022369700000664-main.pdf