Tolong jelaskan mengenai Gambar tambahan dari Helium

The Encyclopedia of the Chemical Elements, disunting oleh Cifford A. Hampel, "Helium" artikel oleh L. W. Brandt (New York; Reinhold Book Corporation; 1968; halaman 256-267) Library of Congress Catalog Card Number: 68-29938

Los Alamos National Laboratory (LANL.gov): Periodic Table, "Helium"  (ditilik pada 10 Oktober 2002 dan 25 Maret 2005)

Guide to the Elements: Revised Edition, oleh Albert Stwertka (New York; Oxford University Press; 1998; halaman 22-24) ISBN 0-19-512708-0

The Elements: Third Edition, oleh John Emsley (New York; Oxford University Press; 1998; halaman 94-95) ISBN 0-19-855818-X

United States Geological Survei (usgs.gov): Mineral Information for Helium  (ditilik 31 Maret 2005)

The thermosphere: a part of the heterosphere, oleh J. Vercheval   (ditilik 1 Apr 2005)

Isotopic Composition and Abundance of Interstellar Neutral Helium Based on Direct Measurements, Zastenker G.N. et al., , dipublikasikan di Astrophysics, April 2002, vol. 45, no. 2, pp. 131–142(12)

Dynamic and thermodynamic properties of solid helium in the reduced all-neighbours approximation of the self-consistent phonon theory, C. Malinowska-Adamska, P. Sŀoma, J. Tomaszewski, physica status solidi (b), Volume 240, Issue 1, Halaman 55 - 67; Diterbitkan secara Online: 19 Sep 2003

The Two Fluid Model of Superfluid Helium, S. Yuan, (ditilik 4 Apr 2005)

Rollin Film Rates in Liquid Helium, Henry A. Fairbank dan C. T. Lane, Phys. Rev. 76, 1209–1211 (1949), dari arsip online

Introduction to Liquid Helium , pada the NASA Goddard Space Flight Center (ditilik 4 Apr 2005)

Tests of vacuum VS helium in a solar telescope, Engvold, O.; Dunn, R. B.; Smartt, R. N.; Livingston, W. C.. Applied Optics, vol. 22, Jan. 1, 1983, p. 10-12.

Helium: Fundamental models, Don L. Anderson, G. R. Foulger & Anders Meibom (ditilik 5 Apr 2005)

High Pressure Nervous Syndrome'', Diving Medicine Online (ditilik 5 Apr 2005)