Telephone numbers in Singapore digits. Five digits were introduced in 1960s, whereas 5-digit and 6-digit phone numbers were introduced in 1960s as fixed lines grew, but in that year, these changed to seven digits as the introduction of new towns arose (Tampines, Jurong East, Bukit Batok, Yishun and Hougang) and a large number of new numbers were required. Rationalisation was based on geographical locale over the 12 years. In 1995, the digit '9' was added to the front of mobiland pager numbers, making numbers eight digits, and on 1 March 2002, the digit '6' was added to the front of existing fixed line telephone
Passenger to Frankfurt copper, goldmines in South Africa, armaments in Sweden, uranium deposits, nuclear developments, and "vast stretches" of cobalt. The book has been published continuously since 1970 and up to 2018, in English and other languages, per the list of books held at libraries in WorldCat. The International Standard Book Number (ISBN) system was introduced in 1970 by the International Standards Organization (ISO), and this is the first Agatha Christie novel to have an ISBN on the first edition. Re-issues published in 1970 or later of her earlier novels have the ISBN issued and appears on the book, but not the first