Mainly natural numbers :
a few elementary studies on Smarandache sequences and other number problems /
Henry Ibstedt.
APA Citation
Ibstedt, H. (2003). Mainly natural numbers: a few elementary studies on Smarandache sequences and other number problems. Martinsville, Ind.: Bookman Pub..
MLA Citation
Ibstedt, Henry. Mainly Natural Numbers: a Few Elementary Studies On Smarandache Sequences And Other Number Problems. Martinsville, Ind.: Bookman Pub., 2003.
Warning: These citations may not always be complete (especially for serials).