7.20.2 Greatest hits from previous weeks

7.20.2.1 Package natbib Error: Bibliography not compatible with author-year citations

https://tex.stackexchange.com/landing/r/digest?cta=question&id=54480

I have a basic tex file and a bibliography which is exported from Mendeley 
However, when I want to cite in the author-year style, I get the error: 
Package natbib Error: Bibliography not compatible ... 
[bibtex] [errors] [natbib]
 

asked by grrrbytes https://tex.stackexchange.com/landing/r/digest?cta=user&id=13217 231 votes

answered by Josh Porter https://tex.stackexchange.com/landing/r/digest?cta=user&id=15128 126 votes

7.20.2.2 How to write 'A~\[Currency]' and other umlauts and accented letters in bibliography?

https://tex.stackexchange.com/landing/r/digest?cta=question&id=57743

How to write in bibliography (package natbib) letter "a" with two dots above? Specially, I mean the word BirkhA~\[Currency]user. 
Is there a general rule or way how to write such umlauts or other accented letters ... 
[bibtex] [accents] [characters]
 

asked by Laura https://tex.stackexchange.com/landing/r/digest?cta=user&id=14475 376 votes

answered by Mico https://tex.stackexchange.com/landing/r/digest?cta=user&id=5001 501 votes

7.20.2.3 How to write cases with LaTeX?

https://tex.stackexchange.com/landing/r/digest?cta=question&id=240868

The code i used to write 
is this one 
$$ 
X(m,n)= 
\begin{cases} 
x(n),\\ 
x(n-1)\\ 
x(n-1) 
\end{cases} 
$$ 
But I don't know how to write this one 
I appreciate any help. 
Edited: I'm sorry to add this ... 
[math-mode] [cases]
 

asked by MaryA~ https://tex.stackexchange.com/landing/r/digest?cta=user&id=65856 164 votes

answered by Ignasi https://tex.stackexchange.com/landing/r/digest?cta=user&id=1952 120 votes

7.20.2.4 BibTeX loses capitals when creating .bbl file

https://tex.stackexchange.com/landing/r/digest?cta=question&id=10772

Titles of articles I'm about to cite contain upper case letters and when using BibTeX it converts them to lower case ones. This happens only in the title and only the first letter conserves its case. ... 
[bibtex] [capitalization]
 

asked by Crowley https://tex.stackexchange.com/landing/r/digest?cta=user&id=649 291 votes

answered by Yossi Gil https://tex.stackexchange.com/landing/r/digest?cta=user&id=3391 293 votes

7.20.2.5 Using the \tab Command

https://tex.stackexchange.com/landing/r/digest?cta=question&id=198432

I have seen several cases of people using the \tab command to insert a specific amount of space between objects (as opposed to the \hfill command which uses any remaining space).  However, I have ... 
[spacing]
 

asked by Mathematician https://tex.stackexchange.com/landing/r/digest?cta=user&id=49199 73 votes

answered by Mathematician https://tex.stackexchange.com/landing/r/digest?cta=user&id=49199 85 votes

7.20.2.6 How can I split an equation over two (or more) lines

https://tex.stackexchange.com/landing/r/digest?cta=question&id=3782

I am having the following equation: 
\begin{equation} 
Q(\lambda,\hat{\lambda}) = -\frac{1}{2} P(O \mid \lambda ) \sum_s \sum_m \sum_t \gamma_m^{(s)} (t) \left( n \log(2 \pi ) + \log \left| C_m^{(s)} ... 
[math-mode] [equations] [line-breaking] [breqn]
 

asked by Peter Smit https://tex.stackexchange.com/landing/r/digest?cta=user&id=459 283 votes

answered by Will Robertson https://tex.stackexchange.com/landing/r/digest?cta=user&id=179 185 votes

7.20.2.7 How to write two dot above a letter?

https://tex.stackexchange.com/landing/r/digest?cta=question&id=152951

the two dots above a letter represents two derivative of varible t. 
My method: 
\documentclass[UTF8]{ctexart} 
\usepackage{amsmath} 
\usepackage{amssymb} 
\usepackage{graphicx} 
\usepackage{epstopdf} 
\... 
[math-mode] [accents]
 

asked by mma https://tex.stackexchange.com/landing/r/digest?cta=user&id=43727 110 votes

answered by Cain https://tex.stackexchange.com/landing/r/digest?cta=user&id=28428 153 votes