APA (7th ed.) Citation

Dillenburg, D. (2004). But that was then, and this is now. Sociedade Brasileira de Física.

Chicago Style (17th ed.) Citation

Dillenburg, Darcy. But That Was Then, and This Is Now. Sociedade Brasileira de Física, 2004.

MLA (9th ed.) Citation

Dillenburg, Darcy. But That Was Then, and This Is Now. Sociedade Brasileira de Física, 2004.

Warning: These citations may not always be 100% accurate.